When using scales 7 and above and Comp !=2 , the process goes to 98-99% then it sits there....
Forever and ever...
The program does NOT become unresponsive. I can abort the process, no problem.
The value of Comp may be circumstantial, but out of the few tests I ran (as you can imagine I didn't run all possible combinations!), when Comp=2 I always got an image, even with Scale=12 which of course it's the slowest of all.