Deluge
Using Windows version of 0.5.6.96. When I went to Help ==> About, you get the little About Deluge window. If you click on either the License or Credits button then the little window disappears but you can not activate anything else. It is like a freeze but down or uploads just continue. If you rightclick on the Deluge icon in the systemtray then the little window comes back again and after one or more clicks you can close the screen.
Hope to have been of any help.