Due to unforeseen technical problems, the site customisation options have gone haywire and are now refusing to function correctly. I have now reset everyone's profiles in the hope that this will cure the problem - but I can't be sure that it has worked.
If you have customised the site in the past, then please try doing it again and with any luck it should now work. If not, please drop me an e-mail with the details of the problems you're having.
If things still continue to fail I'll disable the customisation facility until it's working correctly.