At first I was getting eggs in 90% of the nests. Now It is back to 30%, as it was exactly without the mod.
Let me show what I edited in the script:
I took out the remark lines.
I will load it up tonight and see what happens. I did notice something right away, at the very bottom (right above </config>, you forgot to remove the --> (end of the comment). Not sure if that will cause an issue, but I will leave it in for now to see what I see on my end.
For testing purposes, I will also change the resourceFeather in the second group to another item so it shows clearly what is being picked when a birdnest is looted. That line for bird feathers has a high priority (high) compared to the egg line which is medHigh based on my code.
If the code is loading correctly, there just might be fine tuning that needs to be done on the probabilities (which is what I am thinking needs to be done for your purposes). One thing I could do is change the code from:
<lootgroup name="groupBirdNest01" count="1">
<item name="resourceFeather" count="1"/>
</lootgroup>
<lootgroup name="groupBirdNest02" count="1,2">
<item name="foodEgg" loot_prob_template="medHigh"/>
<item name="resourceFeather" count="1,5" loot_prob_template="high"/>
</lootgroup>
<lootgroup name="groupBirdNest" count="all">
<item group="groupBirdNest01" count="1"/>
<item group="groupBirdNest02" count="1"/>
</lootgroup>
to this:
<lootgroup name="groupBirdNest01" count="1">
<item name="resourceFeather" count="1,3"/>
</lootgroup>
<lootgroup name="groupBirdNest02" count="1,2">
<item name="foodEgg" loot_prob_template="med"/>
<item name="resourceFeather" count="1,3" loot_prob_template="med"/>
</lootgroup>
<lootgroup name="groupBirdNest" count="all">
<item group="groupBirdNest01" count="1"/>
<item group="groupBirdNest02" count="1"/>
</lootgroup>
That effectively change the chances to 50/50 in the second group of getting an egg.