Ok, there may have been some very odd glitches going on in the last 1-2 hours to do with styles. I've managed to sort out the DB mess that was preventing multiple-theme switching to work, so now the default and subSilver are interchangeable.
If your forum used to be black-background and its now white, and you want to change back, go to Profile, scroll to "Board Style" and set it to "maidenWorld".
If your forum used to be white-background and its now black, and you want to change back, go to Profile, scroll to "Board Style" and set it to "subSilver".
I'll be working on subSilver to make it more customized for the site as soon as possible, and translating the buttons from the default design to finnish.
Thanks