Hi Steve and Rich,
I have been testing this issue on a couple of different Macs. I have not been able to reproduce the problem yet (don't worry, I am very sensitive to timing).
I am curious about the exact build version of Band-in-a-Box that you are using. Can you please find out by clicking on the Band-in-a-Box menu and clicking on "About Band-in-a-Box"?
The version that I am using is 2011 Build 26.
Another thing to consider is if you have the latest RealDrums updates. If you installed a full UltraPAK or something similar (installed Band-in-a-Box as well as all of the RealDrums) recently, you probably have the latest updates. To be sure, you can just install the full RealDrums update patch. Here is a download link:
http://www.pgmusic.com/support_macintosh_realdrums.htm#RealDrums01-29Also, does the timing problem exist still if you render the song? (to WAV, AIFF, or M4A format)