EQ2Interface - Switch to "Tech Grey Light" theme does not stick

On my home computer I have the Forum theme set to "Tech Grey Light", which I prefer. On my work machine, it is set to the 'Dark' theme. I cannot seem to clear the dark theme on my work machine.

Things I've tried:
- Switching the style using the quick style picker at the bottom of the screen. It changes the display style of the current screen, but switching to another screen resets back to the dark theme. Quick Switching also generates a new cookie for 'eq2interface.com', with a contents of "bbstyleid 1". This matches the value of the option in the webpage source.

- Changing the default theme in my User CP. It has been set to the "Tech Grey Light" for some time now. I have switched it back and forth a number of times with no effect.

- Deleting all eq2interface cookies. I note that I orginally had 2 cookies, one for www.eq2interface.com and another for eq2interface.com

Interestingly, the original cookies had login info, but the new one does not, yet I am showing at logged in. This suggests to me that there may be a cookie path issue, or possibly the domain that is issuing the cookie is different than the URL I'm using.

Other interesting effects -
I cannot log out. Pressing logout generates initially generates an error. I try it again and it says all cookies cleared (which they are not), and I am STILL logged in.

Note that I am sorting my cookies by date/time, so I SHOULD be able to tell if there is still another cookie.

Anyway, I really want the Grey theme and it's starting to drive me a little crazy. Help.