I have used RB to collaborate with other musicians who don't use it. All I did was save each track that I used as a wav file and sent those. For the chords, I just created a video for them. (as pipeline noted).

The only thing you have to worry about is getting the tracks to line up. If you have a track that wasn't recorded from the beginning of the song, use the "consolidate audio region" from the tracks menu. This will add "silence" to fill out the track.