So I was playing today and unlocked the non stop skill for reaching karma level 4 but then I went to play co op and afterwards when I looked at my skill tree again it was locked saying I had to level up 2 more times but I'm still karma level 4 what gives?
I have this exact same problem, I'm karma level 6 (I recently unlocked the shredder) and while I'm sure the non-stop skill was unlocked previously, it's locked now. I've gained a bit of karma but nothing, and I have a long way to go to get to karma level 7 to check if that fixes it. Uncool for such an important skill!