Cubase 12 Import tracks from Project not working

HI.
When i use “import tracks from project” Channel settings in C12, it only imports one track then deletes the other tracks. Totally works on C11.
Been quite disappointed with C12. Loads of show stopping bugs. C11 was super stable. What could have broken in the process?

Which?
Most things work smooth here…
Problems with some NI stuff, but that’s it.

When I import tracks from project I get a “Cubase has a serious error” dialog box then all the tracks I was importing to (bar one) remove themselves.
I’ll try to keep each show stopping bugs to their own thread.
Thanks

Crash dump says “the thread tried to read from or write to a virtual address for which it does not have the appropriate access”