Have you tried plugging the master keyboard into the sonar laptop and passing through notes i.e. keyboard->sonar->qlc?

When I put the masterkeyboard through sonar, it all freezes. When I try to play back a sequence from sonar it all freezes. Both after 1 MIDI -note. When I plug the masterkeyboard directly to the MIDI -interface on the. Qlc-machine everything works perfect. That's why I don't think it's a qlc-problem. Maybe it's the creamware MIDI-interface on my sonarmachine who is the guilty scumbag here.... 

Try using loopmidi to set up virtual midi ports and qlc on the sonar machine and run only that one laptop.