You want it to play in the system Windows Media Player as BIab can't use an external app on the system files that come with WMP. So try it in the actual system WMP.
This was the major problem running on Linux under Wine, Biab was determined to use Window Media Player system files that you don't have in Wine, same with the BBPlugin.
This is all the more reason Biab needs it's own internal wma player that plays through the Biab audio device.

This Plays instantly now without any lag using the internal player rather than Windows Media Player:
https://www.dropbox.com/s/l9peeglgt7ovwir/Reaper-Biab-Drums-Preview.mp4?dl=0

You should have these system files

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