RM 1.0 Set view/access permission for RM?

If I leave all permissions to "not set" the users will not see the Resource Manager, not even the tab? The reason I'm asking is because I want to install it and then configure it properly before users start exploring it.
One addition to this, would it be possible to set these permissions per category? I have some categories which contain private material that only members of certain groups may see (and even may see that there is a resource at all in addition to being able to download it).