you should have a try with MSC over rtpMidi. Qlab can send MSC. Just activate MSC in the Midi settings of M-PC. I trigger the cues in M-PC with MSC from a similar software like qLab (Show Cue System on PC).
Have a look at this post: http://forum.martin.com/t/solved-triggering-cues-via-midi-commands-or-alternative-osc-from-another-software-on-the-same-pc/3580/5
I have used OS and iOS software to send Midi over network to different software on a Windows PC. Worked perfect for me. I did not yet send MSC commands over network with rtpMidi, but i presume it will work aswell.
If it works, please give a little feedback, so maybe i gonna use this with qLab in the future also.