Fantastic work, the new UI looks great, and it’s definitely more responsive than the old.
1) I don’t know if this was true before the new UI, but I’ve switched steam’s FPS counter on and found that BB was trying to melt my graphics card with over 300 fps. Ticking the game’s Vsync option and restarting brought things back into line at 60 fps. Maybe limit the frame rate or have Vsync enabled by default?
2) After playing for half an hour or so I had an odd glitch where the mouse pointer sprite stopped moving: I could still select menu options with my mouse to save and quit, but it was rather tricky without the visual feedback of the mouse pointer (which just stayed stuck near the middle of the screen). This never happened in the main code branch.