Unless you need some of the features available in BIAB and not Real Band just load the file directly into RB. Then while listing to it place your part markers were you want them. Then delete the tracks you don't want and add the Real tracks that you do. This is how I do It. I usually only keep the piano part or whatever instrument that may play a phrase that's the hook of the tune.

John
ESI Gigaport HD+
Lenovo Turion II /4 Gig Ram/ Win7x64 be
15.6" Monitor
"The only Band is a Real Band"
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