Using the CF_Preview API allows the BBPlugin to play back the "Bass - 1255 Bass, Electric, PopShiningA-B Ev 120.di" track files direct inside the Plugin and follow any varying tempo map as in the demo script you can seek instantly and change the playback rate on the fly.

So you have all the section info source/rate/pitch etc.. listed in the "Bass - 1255 Bass, Electric, PopShiningA-B Ev 120.di" ready to Play with the Play button in the Plugin or sync play to any tempo map in Reaper, it just makes it all too easy for you.
Sure this would be good if you could do this natively in the BBPlugin/BBPlugin Standalone but for now it's an easy way to get it going with Reaper then maybe you can develop it natively internally to give all DAWs the speed.

<ITEM
POSITION 6.89
SNAPOFFS 0
LENGTH 6.83928571428572
SOFFS 28.0383333333333
PLAYRATE 1.16666666666667 1 0 -1 0 0.0025
<SOURCE VIDEO
FILE "E:\bb\RealTracks\Bass, Electric, PopShiningA-B Ev 120\bs2126.wma"
>
>