If your Biab song has tempo or time signature changes just drag in a midi/RC to Reaper first, this will also give you the chords as markers.
Some songs maybe using a different timebase track or you actually selected a different timebase:

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you should get a prompt to ask the timebase of the track, so it's using a third timebase, the instrument is 40bpm but song is 120bpm so 3 is selected (see below)

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