I googled the web, but I didn't find anything about GIMP in terms of what you've explained above. Based on the available data, I've found out that users have issues with the Copy and Paste function. You have to use Copy Visible for it to crop/copy properly.
Another thing is to use the Extras version of the software. As for your inquiry, go to the options menu and access its preferences to see if the hotkeys can be changed somehow.