What do you mean by CB Privacy doesn't work? There's no privacy controls in frontend profile edit? There's no privacy integration parameters in Tab or Field management?
What Joomla version are you using? We're back to having to support 2 major releases of Joomla so it'd be a huge help if everyone always reports if they're using J3 or J4 so we don't have to ask this with every post.
when going to a field, the "integrations" shows up and then disappears.
A tab normally does that when it's empty.
Does reinstalling community builder over the nightly build mean that I have to start all over again with my setup?
Nope, you're just updating CB and won't have to start anything over.