I doubt that's it. The only time I've ever seen localization.txt require an entry is when its trying to display requirements for each level of a perk, but that just throws a null ref when you hover your mouse over the perk.
Can you post your xml? I would suspect you're doing something like adding a new Skill and the parent attribute doesn't exist, and that's what its not liking. But that's a wild guess.
Here's what I have done in the progression.xml so far. I have tried to comment out sections and just run bits at a time, but it still gives me the same error.
The general idea of these changes is to replace the Perception attribute with Dexterity. I am also restructuring perks so that each attribute has a melee and a ranges combat, then some number of crafting and talent perks. I am starting to think that this idea is better off as a full overhaul than a series of modlets, since I'm spending 75% of my time trying to get the changes made via xPath rather than installing the content that I want. Thank you in advance for the assistance.
<!--
- Replaced Perception attribute with Dexterity (10/17/2020)
- Created generic Combat, Crafting, and Talent skills (10/18/2020)
- Created perks for Dexterity: Blades, Long Rifles (10/18/2020)
-->
<config>
<!-- Attributes -->
<insertBefore xpath="/progression/attributes/attribute[@name='attIntellect']">
<attribute name="attDexterity" name_key="attDexterityName" desc_key="attDexterityDesc" icon="ui_game_symbol_stealth">
<level_requirements level="1"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints01"/></level_requirements>
<level_requirements level="2"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints01"/></level_requirements>
<level_requirements level="3"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints01"/></level_requirements>
<level_requirements level="4"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints01"/></level_requirements>
<level_requirements level="5"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints01"/></level_requirements>
<level_requirements level="6"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints02"/></level_requirements>
<level_requirements level="7"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints02"/></level_requirements>
<level_requirements level="8"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints02"/></level_requirements>
<level_requirements level="9"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints03"/></level_requirements>
<level_requirements level="10"><requirement name="PlayerLevel" operation="GTE" value="1" desc_key="reqGenericPoints04"/></level_requirements>
<effect_group>
<requirement name="ItemHasTags" tags="attDexterity"/>
<passive_effect name="DamageModifier" operation="perc_add" level="2,8" value="0.1,.7" tags="head"/>
<passive_effect name="DamageModifier" operation="perc_add" level="9,10" value=".85,1" tags="head"/>
<passive_effect name="DismemberChance" operation="base_add" level="2,10" value=".05,.45"/>
<effect_description level="1" desc_key="attDexterityRank01Desc" long_desc_key="attDexterityRank01LongDesc"/>
<effect_description level="2" desc_key="attDexterityRank02Desc" long_desc_key="attDexterityRank02LongDesc"/>
<effect_description level="3" desc_key="attDexterityRank03Desc" long_desc_key="attDexterityRank03LongDesc"/>
<effect_description level="4" desc_key="attDexterityRank04Desc" long_desc_key="attDexterityRank04LongDesc"/>
<effect_description level="5" desc_key="attDexterityRank05Desc" long_desc_key="attDexterityRank05LongDesc"/>
<effect_description level="6" desc_key="attDexterityRank06Desc" long_desc_key="attDexterityRank06LongDesc"/>
<effect_description level="7" desc_key="attDexterityRank07Desc" long_desc_key="attDexterityRank07LongDesc"/>
<effect_description level="8" desc_key="attDexterityRank08Desc" long_desc_key="attDexterityRank08LongDesc"/>
<effect_description level="9" desc_key="attDexterityRank09Desc" long_desc_key="attDexterityRank09LongDesc"/>
<effect_description level="10" desc_key="attDexterityRank10Desc" long_desc_key="attDexterityRank10LongDesc"/>
</effect_group>
</attribute>
</insertBefore>
<remove xpath="/progression/attributes/attribute[@name='attPerception']"/>
<!-- Skills -->
<remove xpath="/progression/skills/skill[@name='skillPerceptionCombat']"/>
<remove xpath="/progression/skills/skill[@name='skillPerceptionGeneral']"/>
<remove xpath="/progression/skills/skill[@name='skillPerceptionScavenging']"/>
<append xpath="/progression/skills">
<skill name="skillDexterityCombat" parent="attDexterity" name_key="skillCombatPerksName" desc_key="skillCombatPerksDesc" icon="ui_game_symbol_marksmanship"></skill>
<skill name="skillDexterityCrafting" parent="attDexterity" name_key="skillCraftingPerksName" desc_key="skillCraftingPerksDesc" icon="ui_game_symbol_misc_crafting"></skill>
<skill name="skillDexterityTalent" parent="attDexterity" name_key="skillTalentPerksName" desc_key="skillTalentPerksDesc" icon="ui_game_symbol_hand"></skill>
</append>
<!--
<append xpath="/progression/skills">
<skill name="skillStrengthCombat" parent="attStrength" name_key="skillCombatPerksName" desc_key="skillCombatPerksDesc" icon="ui_game_symbol_marksmanship"></skill>
<skill name="skillStrengthCrafting" parent="attStrength" name_key="skillCraftingPerksName" desc_key="skillCraftingPerkDesc" icon="ui_game_symbol_misc_crafting"></skill>
<skill name="skillStrengthTalent" parent="attStrength" name_key="skillTalentPerksName" desc_key="skillTalentPerkDesc" icon="ui_game_symbol_resource"></skill>
</append>
<append xpath="/progression/skills">
<skill name="skillFortitudeCombat" parent="attFortitude" name_key="skillCombatPerksName" desc_key="skillCombatPerksDesc" icon="ui_game_symbol_marksmanship"></skill>
<skill name="skillFortitudeCrafting" parent="attFortitude" name_key="skillCraftingPerksName" desc_key="skillCraftingPerkDesc" icon="ui_game_symbol_misc_crafting"></skill>
<skill name="skillFortitudeTalent" parent="attFortitude" name_key="skillTalentPerksName" desc_key="skillTalentPerkDesc" icon="ui_game_symbol_water"></skill>
</append>
<append xpath="/progression/skills">
<skill name="skillAgilityCombat" parent="attAgility" name_key="skillCombatPerksName" desc_key="skillCombatPerksDesc" icon="ui_game_symbol_marksmanship"></skill>
<skill name="skillAgilityCrafting" parent="attAgility" name_key="skillCraftingPerksName" desc_key="skillCraftingPerkDesc" icon="ui_game_symbol_misc_crafting"></skill>
<skill name="skillAgilityTalent" parent="attAgility" name_key="skillTalentPerksName" desc_key="skillTalentPerkDesc" icon="ui_game_symbol_stealth2"></skill>
</append>
<append xpath="/progression/skills">
<skill name="skillIntellectCombat" parent="attIntellect" name_key="skillCombatPerksName" desc_key="skillCombatPerksDesc" icon="ui_game_symbol_marksmanship"></skill>
<skill name="skillIntellectCrafting" parent="attIntellect" name_key="skillCraftingPerksName" desc_key="skillCraftingPerkDesc" icon="ui_game_symbol_misc_crafting"></skill>
<skill name="skillIntellectTalent" parent="attIntellect" name_key="skillTalentPerksName" desc_key="skillTalentPerkDesc" icon="ui_game_symbol_misc_crafting"></skill>
</append>
-->
<!-- Perks -->
<remove xpath="/progression/perks/perk[@name='perkDeadEye']"/>
<remove xpath="/progression/perks/perk[@name='perkDemolitionsExpert']"/>
<remove xpath="/progression/perks/perk[@name='perkJavelinMaster']"/>
<append xpath="/progression/perks">
<perk name="perkBlades" parent="skillDexterityCombat" name_key="perkBladesName" desc_key="perkBladesDesc" icon="ui_game_symbol_deep_cuts">
<level_requirements level="1"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="1" desc_key="reqDexterityLevel01"/></level_requirements>
<level_requirements level="2"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="3" desc_key="reqDexterityLevel03"/></level_requirements>
<level_requirements level="3"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="5" desc_key="reqDexterityLevel05"/></level_requirements>
<level_requirements level="4"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="7" desc_key="reqDexterityLevel07"/></level_requirements>
<level_requirements level="5"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="10" desc_key="reqDexterityLevel10"/></level_requirements>
<effect_group>
<passive_effect name="CraftingTier" operation="base_add" level="1,2,3,4,5" value="1,2,3,4,4" tags="perkBlades"/>
<passive_effect name="RecipeTagUnlocked" operation="base_set" level="1,5" value="1" tags="meleeWpnBladeT1HuntingKnife"/>
<passive_effect name="BlockDamage" operation="perc_add" level="1,5" value=".2,1" tags="perkBlades"/>
<passive_effect name="EntityDamage" operation="perc_add" level="1,5" value=".1,.5" tags="perkBlades"/>
<effect_description level="1" desc_key="perkBladesRank1Desc" long_desc_key="perkBladesRank1LongDesc"/>
<effect_description level="2" desc_key="perkBladesRank2Desc" long_desc_key="perkBladesRank2LongDesc"/>
<effect_description level="3" desc_key="perkBladesRank3Desc" long_desc_key="perkBladesRank3LongDesc"/>
<effect_description level="4" desc_key="perkBladesRank4Desc" long_desc_key="perkBladesRank4LongDesc"/>
<effect_description level="5" desc_key="perkBladesRank5Desc" long_desc_key="perkBladesRank5LongDesc"/>
</effect_group>
<effect_group name="primary, always">
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="@$maxBleedCounter" target="other"/>
<requirement name="ItemHasTags" tags="perkBlades"/>
<triggered_effect trigger="onSelfPrimaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="1"/>
</effect_group>
<effect_group>
<!-- all attacks refresh / extend bleeding even if no stacks can be added -->
<requirement name="ItemHasTags" tags="perkBlades"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="GT" value="0" target="other"/>
<triggered_effect trigger="onSelfPrimaryActionRayHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
</effect_group>
<effect_group name="Secondary">
<requirement name="ItemHasTags" tags="perkBlades"/>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="set" value="2">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="0"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="2" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="set" value="3">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="1"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="Equals" value="2" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="2">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="1"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="2" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="set" value="4">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="2"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="GTE" value="1" target="other"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="4" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="3">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="2"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="2" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="set" value="5">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="3"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="GTE" value="1" target="other"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="5" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="4">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="3"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="2" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="set" value="6">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="4"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="GTE" value="2" target="other"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="6" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="4">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="4"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="2" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="set" value="7">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="5"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="GTE" value="2" target="other"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="7" target="other"/>
</triggered_effect>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="5">
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="5"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="2" target="other"/>
</triggered_effect>
</effect_group>
<effect_group>
<requirement name="ItemHasTags" tags="perkBlades"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="GTE" value="1"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="LT" value="3"/>
<requirement name="CVarCompare" cvar="$bleedSlowdown" operation="GT" value="-.1" target="other"/>
<triggered_effect trigger="onSelfPrimaryActionRayHit" action="ModifyCVar" target="other" cvar="$bleedSlowdown" operation="set" value="-.1"/>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="$bleedSlowdown" operation="set" value="-.1"/>
</effect_group>
<effect_group>
<requirement name="ItemHasTags" tags="perkBlades"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="GTE" value="3"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="LT" value="5"/>
<requirement name="CVarCompare" cvar="$bleedSlowdown" operation="GT" value="-.15" target="other"/>
<triggered_effect trigger="onSelfPrimaryActionRayHit" action="ModifyCVar" target="other" cvar="$bleedSlowdown" operation="set" value="-.15"/>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="$bleedSlowdown" operation="set" value="-.15"/>
</effect_group>
<effect_group>
<requirement name="ItemHasTags" tags="perkBlades"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="5"/>
<requirement name="CVarCompare" cvar="$bleedSlowdown" operation="GT" value="-.2" target="other"/>
<triggered_effect trigger="onSelfPrimaryActionRayHit" action="ModifyCVar" target="other" cvar="$bleedSlowdown" operation="set" value="-.2"/>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="ModifyCVar" target="other" cvar="$bleedSlowdown" operation="set" value="-.2"/>
</effect_group>
<effect_group name="grazing hits T3">
<requirement name="ItemHasTags" tags="perkBlades"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="3"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="5" target="other"/>
<requirement name="RandomRoll" seed_type="Random" min_max="0,100" operation="LTE" value="40"/>
<triggered_effect trigger="onSelfPrimaryActionGrazeHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="1"/>
<triggered_effect trigger="onSelfSecondaryActionGrazeHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="1"/>
<triggered_effect trigger="onSelfPrimaryActionGrazeHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
<triggered_effect trigger="onSelfSecondaryActionGrazeHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
</effect_group>
<effect_group name="grazing hits T4">
<requirement name="ItemHasTags" tags="perkBlades"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="4"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="6" target="other"/>
<requirement name="RandomRoll" seed_type="Random" min_max="0,100" operation="LTE" value="70"/>
<triggered_effect trigger="onSelfPrimaryActionGrazeHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="1"/>
<triggered_effect trigger="onSelfSecondaryActionGrazeHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="1"/>
<triggered_effect trigger="onSelfPrimaryActionGrazeHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
<triggered_effect trigger="onSelfSecondaryActionGrazeHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
</effect_group>
<effect_group name="grazing hits T5">
<requirement name="ItemHasTags" tags="perkBlades"/>
<requirement name="ProgressionLevel" progression_name="perkBlades" operation="Equals" value="5"/>
<requirement name="CVarCompare" cvar="bleedCounter" operation="LT" value="7" target="other"/>
<triggered_effect trigger="onSelfPrimaryActionGrazeHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="1"/>
<triggered_effect trigger="onSelfSecondaryActionGrazeHit" action="ModifyCVar" target="other" cvar="bleedCounter" operation="add" value="1"/>
<triggered_effect trigger="onSelfPrimaryActionGrazeHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
<triggered_effect trigger="onSelfSecondaryActionGrazeHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
</effect_group>
<effect_group>
<requirement name="ItemHasTags" tags="perkBlades"/>
<triggered_effect trigger="onSelfPrimaryActionRayHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
<triggered_effect trigger="onSelfSecondaryActionRayHit" action="AddBuff" target="other" buff="buffInjuryBleeding"/>
</effect_group>
</perk>
<perk name="perkLongRifles" parent="skillDexterityCombat" name_key="perkLongRiflesName" desc_key="perkLongRiflesDesc" icon="ui_game_symbol_map_cursor">
<level_requirements level="1"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="1" desc_key="reqDexterityLevel01"/></level_requirements>
<level_requirements level="2"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="3" desc_key="reqDexterityLevel03"/></level_requirements>
<level_requirements level="3"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="5" desc_key="reqDexterityLevel05"/></level_requirements>
<level_requirements level="4"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="7" desc_key="reqDexterityLevel07"/></level_requirements>
<level_requirements level="5"><requirement name="ProgressionLevel" progression_name="attDexterity" operation="GTE" value="10" desc_key="reqDexterityLevel10"/></level_requirements>
<effect_group>
<passive_effect name="RecipeTagUnlocked" operation="base_set" level="1,5" value="1" tags="gunLongRifleT1BoltActionRifle"/>
<passive_effect name="RecipeTagUnlocked" operation="base_set" level="3,5" value="1" tags="gunLongRifleT2M1Garand"/>
<passive_effect name="CraftingTier" operation="base_add" level="1,2,3,4,5" value="1,2,3,4,4" tags="perkLongRifles"/>
<passive_effect name="EntityDamage" operation="perc_add" level="1,5" value=".1,.5" tags="perkLongRifles"/>
<passive_effect name="WeaponHandling" operation="perc_add" level="1,2,3,4,5" value=".1,.2,.32,.45,.60" tags="perkLongRifles"/>
<passive_effect name="ReloadSpeedMultiplier" operation="perc_add" level="1,5" value="0.1,0.3" tags="perkLongRifles"/>
</effect_group>
<effect_group>
<requirement name="ItemHasTags" tags="perkLongRifles"/>
<requirement name="ProgressionLevel" progression_name="perkLongRifles" operation="GTE" value="3"/>
<triggered_effect trigger="onSelfKilledOther" action="AddBuff" buff="buffLongRifles"/>
<effect_description level="1" desc_key="perkLongRiflesRank1Desc" long_desc_key="perkLongRiflesRank1LongDesc" desc_base="Non localized modder descriptions go here"/>
<effect_description level="2" desc_key="perkLongRiflesRank2Desc" long_desc_key="perkLongRiflesRank2LongDesc"/>
<effect_description level="3" desc_key="perkLongRiflesRank3Desc" long_desc_key="perkLongRiflesRank3LongDesc"/>
<effect_description level="4" desc_key="perkLongRiflesRank4Desc" long_desc_key="perkLongRiflesRank4LongDesc"/>
<effect_description level="5" desc_key="perkLongRiflesRank5Desc" long_desc_key="perkLongRiflesRank5LongDesc"/>
</effect_group>
</perk>
</append>
</config>