Tried deleting the cache file, with DWCC closed, and rebooting but when I go back into the page to change the recordset, whilst it doesn't have a red exclamation mark next to it any more, it still throws me the "While executing applyServerBehaviour..." error.
I would add that the eCart object still has the red exclamation mark next to it. Page attached.
PS. Could this issue be causing these problems? - http://www.webassist.com/forums/posts.php?id=33955
We've been speaking to DMXzone and they describe "bad" code in your extensions which, to be honest, is very disappointing particularly considering the problems we're now experiencing.