Since I started to play around with my new Tyros 4, midis and BIAB, I found some differences (no, not the audio recording, that is obvious).

1) If I open a complex midi file on Mac, it plays back intact but you cannot change voices.
2) Same file on Win - you can change voices but whether you do or not, the file does not play back intact - some midi events must be being stripped

I am licensed for both and my current versions are 2010.5 Mac and 2009.5 Win (both with the latest update patches)

Lanny