Olly,
I’ve managed to work out a solution, a sort of work around. I’ve installed a popup plugin wich explains how ordering works and what they can expect after hitting the send button. This popup only shows 1 time when people arive at the orderpage. Not the best way to do things because most people are scared off by a popup screen but for now it works.
Still it would be great to have a separate “thank you” page wich make things just a little smoother.