Bobby, is it after dragging the MIDI into Reaper that the audio didn't play? If so, that is normal. Reaper doesn't automatically assign an instrument or plugin to a track, so the MIDI has nothing to play through. You mentioned that adding Sampletank caused it to work, right? That's what you'd need to do for each track.

As for version 4.0.0 not working in Reaper, the developers are aware of the issues and are looking into them.


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