[kcroyalgm]

It's not unusual to get the "not responding" message. It's usually bogus and its working. And 15 minutes is definitely not enough time to wait. In converting, patience is definitely a virtue.

Another way to proceed:
Move the dat files from the old league folder to another folder and then convert from that folder. Then just copy all the sub folders from the old league to the converted league.

The conversion actually only "converts" the dat files. All the other files (images, box scores, etc) in the sub folders are just copied by the conversion program. Copying all those folders & files takes a long time as you'll see if you copy them yourself instead of converting them.