I think you got me wrong Brian Usergroup Permissions
Registered => All No
Gallery Users => Can Upload = Yes Category Permissions
For Album X (all other permissions are not customized):
Registered => Not Customized
Gallery Users => Customized, Can Upload = No
Now I have a user who is member of Registered and Gallery Users: He can Upload in Album X.
Only if I select Use Custom Permissions for usergroup Registered (without chaning any of them, all set to No) he will not be able to upload there.
And I think this is not the way it should be?