Post Installation - Main Page text in wrong place

Hi;

After installing the message "This module demonstrates how easy it can be to adapt existing code in OSC...." message shows up to the right of the main body and only a "TEXT_MAIN" message appears where I would expect to see the above message.
You can see testsite here: link removed

I have repeated the install steps twice now and can not see my error. Which file do I need to update to corect the issue?

I beleive (pray) this to be quite a simple issue, so I hope someone can help with a quick reply. (Replies in Dutch are also fine).

Thanks for any tips.