Hickory: If "processing is going on for [too long]" when you hit "Post my message", you can be pretty confident that it's caused by a syntax error, especially if you've quoted and particularly edited those quotes. It's happened to me where I didn't notice a stray [ quote ] or [ / quote ]. This is assuming the forum is behaving normally otherwise. Also, as has been said, copy/pasting has never been an issue -- it's a text window.
Edit: aaaaand I just noticed you mentioned starting a new topic. Nothing to see here. Move along, please.
I appreciated the info :) I have been on GoG for years but never really active in the forums until recently, so I was kind of wondering why when I clicked on "Post my message" it would spin and spin. Now I know, and knowing is half the battle!