Hello,
I am really happy with renoise, but I would very much like to see the rewire-function (both master and slave) in renoise.
Huby
Yeah, Renoise acting as ReWire Master would completely rock. I and many others have wished this for years, but it’s probably never going to happen. So just forget it and try to be happy. 
Workaround: Use a midiloopback instead. Got Renoise (Master) working together with Reason and it runs quite smooth. Haven´t managed yet to get the other app acting as master though.
MidiYoke
https://forum.renoise.com/t/syncing-to-cubase-sx/13915