I imported a rubato piano solo midi file into BIAB 2010.5. Can I get the bar lines to line up with the imported notes, labor intensive though that may be? If so, how?
Thanks.

Have a look at Edit > Nudge Chords/Melody. Otherwise use RealBand where you can slide tracks or use Edit > Slide Midi to adjust exactly.

LynB is right, but I think Mel has a situation where the performed music's tempo is constantly varying, not changing suddenly, then holding that tempo for a while, then changing suddenly again. If that were the case, notions like sliding might be OK.

To handle rubato in BIAB, the only thing I can think of is to make a .wav file from the midi file, bring that into BIAB, then employ the Audio Chord Wizard which will do two things - Figures out the chords (not real interested in that right now), and remaps the midi tempo, measure by measure, to match the .wav file (takes some work in ACW to do this). Now, when back in BIAB, the tempo will change every measure to follow the .wav file. You may want to disable styles so the "band" won't play. If you want the band to play, you may need to refine ACW's chord interpretations.

So not an easy process.

Many DAWs will remap midi directly without going the audio (.wav) route, and are not constrained to tempo changes only at the measure, but can be virtually continuous - but also quite messy.

I'll be looking here to see if others have a slick way to do this.