If we want this to be optional per event category, the selection needs to be stored in the categories table in the DB.
I'm not very keen on changing the DB schema only for this purpose.
If in the help for subcats (see Stefan's first post) I change the text from . . .
If, when adding/editing and event, no subcategory has been selected, the event will have the normal category colors in the various views.
to . . .
If, when adding/editing and event, subcategories are available, then a subcategory must be selected.
and leave the code unchanged, the problem is solved
Do you agree?
Roel