Ah,
It is unfortunate that the User upload tool does not know how to assign category level roles in the same way it does system level roles, which would have been an easy way to do this. But there is no existing tool that I know of to assign category level roles en mass.
It is unfortunate that the User upload tool does not know how to assign category level roles in the same way it does system level roles, which would have been an easy way to do this. But there is no existing tool that I know of to assign category level roles en mass.