Seemed that every time when I unlock an achievement the bug happens:
1st - 3rd play: when I was awarded the completed skill tree achievement
4th play: when I was awarded the Lv100 achievement
Interesting. Seems to be related to achievements then. Probably some conflict with the steam PC version causing an issue. Sorry about that.
It's OK. I'm still enjoying this game though. It's really addictive, and I'd still play it to the end even with this "freeze" bug.
Hey, sorry it took so long (didn't think I'd be coming back to this project), but this is fixed now!