Melodyne Problem

I imported an Acid loop (of a vocal) into a Sonar X3 project, then selected the loop and chose Region FX/Melodyne/Create Region FX. When I did so, a screen called Melodyne Licenser popped up. It displayed my Melodyne license number, and said the software was activated. OK, so far so good, although I knew that already. However, the region was grayed out and there were no controls displayed for the Melodyne editor. So I am thus unable to make any changes to the clip. This same problem occurred a few weeks ago and upon the advice of Melodyne tech support I uninstalled/re-installed the program. (As I recall, this did not fix the problem, and I ended up bouncing my tracks to a new project, in which Melodyne for some reason chose to function properly.)
 
I tried bouncing the Acid loop to a clip, thinking maybe Melodyne doesn't play well with Acid loops, but the problem remained. I then started a new Sonar project, imported the same Acid loop, and created a region effect from it. This time all was as normal...no Licenser screen appeared, I could make changes in Melodyne, and the Melodyne tools were present.  I didn't even have to bounce the Acid loop to a clip.
 
Why will Melodyne work in one Sonar project and not in another, using the very same clip in both projects?
 
Thank you.