Control Panel select avatars permission error

Hi,

I have edited register.asp to hide a few of the registration fields from users

I'm hiding everything between realname, gender, location .... and DOB (so all the AIM, ICQ type fields are also hidden). By hiding - what I've done is insert  an impossible if statement <% if 1 = 0 then %>

Then I am hiding the signature boxes and always attach my signature.

When most of the forum members try to edit an avatar - using register.asp?FPN=2 (which now only shows the avatar options) - most are redirected to
insufficient_permission.asp?M=sID page displaying the message:

Only members with sufficient permission can access this page.

A security error has occurred with authentication.

Are some of the fields that I am not displaying required on the page? It's bizarre because some members are able to select an avatar, but most can't. I am unable to - in both Firefox and IE7. I have cleared the cache and cookies but still no success. I've checked the page using Firefox error console and there aren't any javascript errors.

Can anyone give me some ideas what else to try please?

Thanks
Dan

We're not actually using the registration form for registrations (we've got a heavily customised form) - but in the control panel we want to use some of the features like avatars.

I think I might have sorted it now though. I changed the signatures form objects to type=hidden.

Not sure why the error console wasn't reporting the JavaScript error in the CheckForm function though.