Toonboom cannot import or export movs


For work I need to use both Harmony 10 and 11. Oddly I find I can import movs fine into 11, but not into 10. no format, not even ones I could before into harmony 10 before I moved onto a new mac.
This made me think it cant be quicktime or any other external errors, as harmony 11 still works fine, and I went straight to reinstall Harmony 10.
Now Harmony 10 still does not import any video formats, it doesn’t even show a loading bar (to convert into images etc) it just crashes immediately, and when it starts up, it looks different. It simply neglects to load the welcome window so I see an empty grey window instead. However, I CAN open a scene file where someone else in my company imported the video file for me. But it remains a problem if I can never do this for myself.
i also cant EXPORT any test movies… TT___TT
and also some older files I made on old mac (in harmony 10) and on laptop (not mac) also harmony 10 tho… cannot open. THESE R MAJOR ISSUES.

I’ve tried installing older version of quicktime (7) altho didn’t uninstall the new one.
I’ve also tried installing ffmpeg thing separate… tried… not sure it worked.
Haven’t figured out if its changed anything…
The last time i tried to render and waited forever… (to see if anything)
I eventually got an error - about media server…
Something like it could not connect to it? (usually just freezes harmony)

Plz help? Anyone?