hi Phil:
just to make sure that you're not going to encounter problems later: did you upgrade the original board before transferring the data to the clean install of 6.7.3? what version was the old board running?
as for the out of synch errors, go ahead and nuke the ubbaccel_test.php file from the server and re-upload. if you still get the error,
submit a support ticket, and we'll figure out what's up. <img src="https://www.ubbcentral.com/boards/images/graemlins/smile.gif" alt="" />