YES, Biab Plugin needs decimal tempo maps !!
I made up some scripts to do all that in Reaper to fit a constant tempo audio item to the tempo map in Reaper,
but they have now built it into Reaper after some nagging.
You can go into the item properties and set the bpm of the media if it don't get it from the filename or ACID info (you can add ACID in the Biab Plugin Preferences).

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