Hi Mike. I figured it out. For some reason Sonar X3b loaded all my plugins, including "play.vst" from East West.
But X3c did not load the play.vst. And apparently that is probably the file that "hanged" while trying to install X3c.
So I went to soundsonline (EAST WEST) and installed the latest play vst 64 bit. Then I went to Sonar X3 and made sure that the file was included in the scan. It worked. Then I reloaded the X3c software and this time it did not hang.
I love X3C - the latency is so much lower than Sonar 8.5.3.
I am glad I finally had the courage to make the transition.
Best to you,
AB