Some of the threads won't let me unsubscribe... I click the button and a moment later it un-clicks. And I still get email notices.

What button? I don't see any unsubscribe button on the Forum pages.

Do you mean your profile settings on https://www.aptera.us/account/settings ?

From there you should be able to adjust the kind of notifications you get, but I don't see any settings for individual threads. It looks to be all threads or nothing.