I'm using roScreen and the compositor in my app. So far it seems to work ok even though its performance is slow (especially with text)...but yeah you have to do everything from scratch. It seems that Roku doesn't want to really support UI that's outside of their standard screens. I would be very happy as a developer if we could get access to buttons, scrollbars, tables, grids and such directly, but it seems like we have to roll our own. Also, NDK access is limited unless you are porting an existing game (I know because I asked). Good luck.