Maybe it's just me and that I'm new to Coppermine and galleries in general...
Currently (as with v1.4.9), it seems the user has to create an album within each category in order to upload to the gallery and have the upload categorized according to the category list. When the user uploads to that category other than "* My Gallery *", there is no mention of who uploaded the image in the category navigational text as you would see in "User Galleries" without the use of a plugin. Even then the user's name is put over the image, but there's no way to directly see images uploaded by a single user then.
It seems to me that the correlation between user albums and categories are backwards. The user *should* automatically be assigned a Public and Private album upon registration, then inside the album the user can categorize their uploads according to a global category list set by an admin. When uploading the image, the user then sets the category and selects whether the image is public or private so when a viewer is browsing the gallery they could see who's image it is via the navigational text without having to use a plugin.
Otherwise you end up with a user with a multitude of albums depending on how many categories there are when just two (public & private) would suffice. The "User Galleries" category *should* have been set up to be the way to browse uploaded images by User no matter which categories the images were uploaded to.
Any of this make sense?
Note : This pertains more to a multi-user gallery than a single user gallery. In a single-user gallery, this would be moot as viewers would know that the images were uploaded by a single individual.