Official word from Thompson GVG: It might have been nice to extend the DPOP bus selection on over to the re-entry buttons but engineering decided customers didn't need it. I argued this with the software engineer when it was first introduced because I thought it made sense too. I was shot down. They didn't feel anyone would want to use it because the M/Es can be run in Cleanfeed mode or Split M/E mode so having the 'B' side of an M/E selected on a re-entry didn't make much sense, at least not to them. I couldn't come up with a good example of why I wanted it so it never got changed. Sorry, but for now you will need to map a button or press both the "shift" button and the re-entry. If you can present a good reason why you need it I can resubmit my change request. So it is not a bug just not written into the software.

The B side of the M/E is normally on the shifted side of the M/E button. You may have just found a bug that wasn't caught before the release. You might want to see about contacting GV Customer Service so that they can enter this issue in their Bug List.