This utility of Shane's has done the trick spot on, when I change from one to the other in the 'tool' the correct CM opens up every time.
Regarding what you have said Phil.... That didn't work for me mate, I had already tried having CM open before downloading and sometimes it was OK but other times the other CM used to fire up, I'd be sitting there waiting for a download to start up in TS10 CM and all of a sudden TS12 CM would open up.
Regarding what you have said Phil.... That didn't work for me mate, I had already tried having CM open before downloading and sometimes it was OK but other times the other CM used to fire up, I'd be sitting there waiting for a download to start up in TS10 CM and all of a sudden TS12 CM would open up.