Update: I 'fixed' the error by reinstalling Unity multiple times until one time, by works of magic (?) it allowed me to import AC successfully.
However I still would like to know what to do if this happens again as it took me many hours to fix...
Found this thread trying to do the same. You've probably solved your problem by now but I'll leave my solution here in case someone else needs it.
What I did was create two journal elements inside the main journal menu and position them side by sid…