Most likely the shortcut has been changed from Ctrl+C to Ctrl+B. Use steps 1-6 from the article linked below to get to the Hotkeys file. The folder will probably be EasyWorship.v6 instead of v7.
Not make a copy of the HotKeys.ini file and save it to a flash drive or other location. Right click the HotKeys.ini file and select Open With - Notepad. Now compare the top 3 lines to see if they are the same as listed below. I'm thinking that the "ClearScreenKeys=C-67" has been changed to "ClearScreenKeys=C-66". If so, change it to "ClearScreenKeys=C-67" (without the quotes) and save the file. See if that fixes the issue
SlideNextKeys=78, 40, 32
SlidePrevKeys=80, 38, 8