I don't know if it's because I'm on Mac or what, but all of the tabs stay stuck in the top left corner. Ascent Guidance, Landing Guidance, all of them. Try to move them? Nope, they go right back where they came from. Anyone have any idea what's going on?

damn，me too

found solution: look for "mechjeb" in logs and if it says anything about incompatible dll's uninstall the mod for the dll
edit: log?

Faced the same problem. It was solved by reinstalling the mod with CurseForge

these are all install problems