I had trouble renaming some of the DevExpress controls in a web forms application.

I would change the ID property and the new word would just sit there with red, angry text. I don't know why. I hacked around the problem by pulling the thing I wanted to change out to a .txt file, removing it from the web form, removing the tags at the top of the form which start with...

Register TagPrefix="dx"

...and then copying content back into the page with a new name.