I've tried singleplayer and can't figure it out. Let me preface this:
Me and two friends play cooperatively, and split the perks/work in the game. My gamestage is always significantly lower than theirs, so what exactly determines it. One friend will be the crafter/cooker and it's usually not me, I'm more of the looter/miner, whereas our other friend is the sniper/backup miner. Yet despite regularly making stuff with/using crafting stations, my gamestage is significantly lower than theirs, even if we're all in roughly the same gear.
Me and two friends play cooperatively, and split the perks/work in the game. My gamestage is always significantly lower than theirs, so what exactly determines it. One friend will be the crafter/cooker and it's usually not me, I'm more of the looter/miner, whereas our other friend is the sniper/backup miner. Yet despite regularly making stuff with/using crafting stations, my gamestage is significantly lower than theirs, even if we're all in roughly the same gear.