Hello Symen,
(I've moved your topic here, since I understand you're using the Free Edition and we don't provide formal technical support for the Free Edition, although we try to help out a little here if we can.)
Glad to hear you managed to get your USB-MIDI adapter working.
but is there a way to get the sound not out of the pc but out the organ?
If your Viscount organ has an audio input socket to its amplifiers/speakers then you can probably connect an audio lead from the audio line-out socket on your Mac to that input socket on your Viscount.
However, the speakers inside a digital organ aren't necessarily optimal for reproducing 'wet' organ sample sets ('wet' = organs recorded with their real room acoustics) - connecting your Mac's line-out to a hi-fi system or (best) a pair of good-quality studio monitor speakers might give noticeably better results.
Hope that helps.
Best regards, Martin.
Hauptwerk software designer/developer, Milan Digital Audio.