I use Sonar.... Reaper is just as good for working on files.

I will open X1 first, let it grab the ASIO driver and then I open BB and RB.... since they will grab and share the MME driver.

I export the tracks from Real Band into a folder where they are saved. I create a new folder for each song and all the BB/RB tracks and files go into it. It keeps everything in one place.

I click on X1 and simply use the IMPORT AUDIO command to bring the files into X1.

BB will act as a plug in on many DAW's but I never use it like that, nor do I drag and drop the files.... I like to import them.

It works either way but I do not think it will allow recording through BB into Reaper live.... but you can always record live into reaper directly after you have the files in it's tracks.... I do that ALL the time in Sonar. Most of my songs (not all) have one or more live tracks in them that was recorded directly into X1.

You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.