I had a lot of problems with Reaper and the BSP.
I think my own issues came down to Reaper not being able to be controlled by the BSP's clock, and I couldnt get Reaper to listen to the BSP's Roller/Looper, which is what I wanted to do.
I couldnt figure it out tbh. I asked here a few times but didnt really get any further.
Hopefully, this thread will bring some illumination