Multi-category how to check access-rights?

don't know if this is implementable.

Think it is but not sure how to at the moment. Perhaps with an extra function to detect the category's attached to that event and then other then the current groupmember. And then merge the foreign with the allowed category's within the store function.

Can user A delete it's own event if it is attached to a category user A has no edit/delete rights?

good question. Think the category is leading with it and the user should not be able to delete.

Multiple categories are a nice feature but make administration much more complex.

that's one thing for sure and mistakes and unwanted situations can happen.

As we're not well-known at the moment, perhaps the best thing to do is to strip the multi-cat feature aldo that would be a pitty but doing so we can try to integrate the implementation of full user-rights + other things and if everything is working well, then it would be good to take a look if the multi-cat can be integrated.

write a disclaimer

good option.