WYSIWYGs & 'Course Unit Builder' broken.


I am experiencing some strange behaviour with CoursePress Pro, when editing courses.

WYSIWYGs Visual editor seems empty/broken, but Text editor works in a way, however formatting of any sort doesn't work. (I feel there is a larger problem and this is just one thing that is affected).

The drag & drop Course Unit Builder also appears to not work, same issue with the WYSIWYGs in here, and also saving changes made to a unit doesn't save anything and refreshes the page to an empty unit.

I am receiving the following two errors in my console:
Error: no such method 'instance' for menu widget instance
TypeError: undefined is not an object (evaluating 't.fire')

Theme and all plugins are up to date, and I have tried disabling all other plugins to rule out any sort of conflict, but the errors persist.

Thanks in advance!