I just ran into this bug on quest mode on ios when I hit level 31 and everyone got their roles. I was able to work around by selecting a role and a feat, then moving to the "completion" tab, then selecting the next character. Chose role and feat, moved to completion tab, then on to next character and so on (I have a six man team). I had also switched over to phone interface and had turned effects back on, no idea if that made a difference or not.