Gordon:
Thanks for the reply!
First let me clarify if you misunderstood, I want to render a single MP3 file with Band in a Box that has one channel containing BOTH the count-in and the click track with the second channel the accompaniment. Whether BiaB can accomplish this by itself is an answer that has seemed to elude me in my research.
In regards to the XML files, I too use MuseScore and have always been in the habit of exporting the close to 2000 sheets I've created in MuseScore as uncompressed MusicXML files in addition to PDF's. In regards to the cut time confusion, is it the cut time symbol on an MusicXML score that confuses BiaB or 2/2 time in general?
Coincidentally I also use MobileSheets Pro. Its ability to play MP3's when a sheet is opened should work perfectly for my needs. To me the whole set-up appears to be easy and inexpensive as I already have most of what I need with the exception of BiaB, a DI box and a decent patch cable to go from my tablet to the Di box.
One solo gig might actually cover my start-up costs.

However, I don't want to spend those funds unless I'm sure I can do what I want.
Any additional insight is appreciated!