To any weary devs out there.
I found the solution.
There is a bug in the PL_class cache.lvlib.
discover class type.vi has a conditional disable structure changing the behaviour in the run-time engine:
In development, 'classify plclass.vi' is called. In run-time 'indentify classes in memory.vi' is called.
Inside 'classify plclass.vi' (development environment), Get Category.vi is called:
This call is missing inside 'identify classes in memory.vi'. This results in the category inside the class cache being blank. This results in the modules being placed in the 'other' category.
A small modification to 'identify classes in memory.vi' fixes the problem. Add 'Get Category.vi' and bundle the result into the module cache:
Hope this helps someone out there!