First of all, thank you for your great work on Renoise!
OS X 10.11.1 on mid-2012 Macbook Pro.
I've been working on a project in 3.1b5 (32 bit): AU synths (one DrumSpillage and a lot of u-he instances), mostly native effect devices but a few plugins. Works fine.
In 3.1b6 (32 bit):
1) Launch Renoise
2) Choose my project off "Recently Saved" menu
3) After loading time and then "Successfully loaded" message, entire interface (pattern matrix, main area, instrument list, etc.) remains blank.
4) Press spacebar and the music plays.
5) Try other keys and I successfully navigate and edit the song--but I'm doing so "blind" with a blank interface. No part of the interface shows the results of interaction, not even the strip at top.
6) Click [X] to quit. The interface suddenly populates and updates to the present state of the song.
7) Click "Cancel" to go back into song. Now it's frozen again, but dating to the moment I clicked [X].