Hi Frankenbike,
No SM mixmap needed nor midi-ox/loopmidi, although I searched for the mixmap a year ago and couldn't get my hands on it.
You need:
OSCII-bot v3.
http://www.cockos.com/oscii-bot/
OSCII-bot v3 SudioMix+REAPER.txt script for the OSCII-bot v3
OSCII-bot+StudioMix.ReaperOSC script for Reaper OSC
I have attached the necessary files configured for your system.
They will need to placed in the appropriate locations and Reaper midi/osc configured properly to work.
I'm sure you will have questions. As I said before, I am happy to remote into your system to get you sorted. Might be faster than me trying to talk you through the procedure.
Let me know how it goes.
N2N