I am unable to add a signature line via the settings page or change my time zone. Stuck on GMT. Have many MANY efforts at this.

Try this first, and we'll go from there if necessary. Logout of RCU, clear all your cookies and cache, login and try again. If that doesn't work, let me know.

Did all that and all it accomplished is that i lost all my cookies for all of my various accounts.
whenever I try to change something it says: Your Login or Email has been chosen, please try again

If it can't be fixed just say so and I'll live with it. This is second time I've screwed up my cookies trying to fix this. Very annoying.

The key words "Your Login or Email has been chosen, please try again" help me solve this problem for you. Try to edit your signature again now. If it still doesn't work, logout and back in to refresh your session on RCU and it will work.

That got it. Thanks Nathan.

BTW - your server clock is about 2 minutes fast.