Background: I ran into the same issue this morning.
Troubleshooting Steps Taken:
1.) I tried restarting the computer, no change.
2.) I then ran Fusion in Administrator mode but after inputting login credentials, the same snag of "stuck on loading additional modules" issue occurred.
3.) I then tried doing the repair function using the Fusion Service Utility tool, but I was met with an error that two instances of fusion were operating at the same time, so the repair function didn't work.
4.) I disconnected my main display (I run two monitors), and the program was able to run. I then did the repair function using Service Utility and afterwards tried clearing the cache data. After the repair function, Fusion was able to open successfully. So I plugged back in my main monitor. However, once I tried clearing out the cache data, on the second restart of the program, I got stuck again on "loading additional modules."
5.) I unplugged the main monitor once more and then Fusion was able to start normally.
6.) I exited out of Fusion to run the dual monitor test again. So I re-plugged the main monitor and opened Fusion. It worked properly.
SUMMARY: There is definitely a multiple monitor glitch/bug/hiccup occurring. If you have this issue, unplug your monitor and go from there.
I too enjoyed one hour's worth figuring this out...I'm glad this thread was created, just wanted to give back for the next user.