User CP/Register Problem

[Stalis]

Hello,

I have been having this problem for a few months now, but was never too worried about it until a number of members began to complain. On my boards there is a problem with the Register and User CP link showing for different usergroups.
My short term plan was to alter the navbar so both members and guests see the User CP and Register buttons. But this not only looks awful, it crams the navbar with too many buttons making the layout go out of shape in Mozilla Firefox and Internet Explorer.
So, my question is, do any of you know how to fix this problem? I can't see it as being too complex, but I have tried everything and can't seem to get it to work.

Thanks in advance,

Stalis