up

I need the same thing. Has anybody got an idea ?

Dear Daniele, and dear others,

I didn't reply to your posts too quickly for many reasons.
Not only because "What means a moderator status in PWG?" is not clear enough. In fact, moderator is generally used to reduce impact of different purposes or words in forums, it could be for remarks in PWG. Yet, I didn't understand your request like this. You need an administrator status for some categories. As the result, we can find another way to reply to your query.
But also your idea means a lot of change in right admin. Administrator status is and should stay as a special user authorisation that means as defined at a user level and not at a category level.
In addition, upload is an attribute of a category and it is not a role or right.
More than this, it means that we would have to design a complete new Admin menu for Category administrators and this represents a lot of efforts for something which is very reduced in term of new functionalities.

Above all, I can now explain how you can do.
I currently use this strategy for some sites, and this works well.
What's more, it will be easier with 1.5.0 (wait and see).

Strategy:

Create a real category for instance, I call it "ForExternalAdmin".
Autorise UPLOAD on it but set it as Private category.
UPLOAD needs or doesn"t need to be validated (as you want).
Create a (User) Group, I call it "ExternalAdmin". Give to that group the access to "ForExternalAdmin".
(Notice that usage of a group isn't mandatory, and you can manage access user by user as well.)
Now only "ExternalAdmin" would have access to "ForExternalAdmin".

The only thing you have to do is to create a Virtual Category call it "External" for pictures coming via their UPLOAD and
via Admin+Category+Manage and on "ForExternalAdmin"  + Images info

Time to time, Select new pictures and Associate to the category "External", just for a public access or a different private access.

I hope to be clear enough.
And as I said 1.5.0 is improving way to select new pictures and to associate them to any virtual category.

JediRemi wrote:

But if they can upload pictures ... everybody can.

Now, you can see that is not the case. Only people in "ExternalAdmin" can Upload their pictures.

Enjoy and enhance our galleries.