Update: I should state that I can paste something from an external application (like Explorer) into the Procedure Editor, but I cannot copy and paste WITHIN the procedure editor. In other words, if I have a complex folder path, I don't want to re-type it - I want to copy it from one line to another - this is not working.
EDIT: So to clarify, it appears that copying FROM the procedure editor is what is not working in 6.3