YOU READ MY ARTICLE!!! YAY!!!
Anyway....
So, the article helped you. Great. That was what I was going to point you towards. The admin interface isn't that hard. You need 3 items:
1.) Forms
2.) Processing pages
3.) Validation/Verification Processes
Now, for the admin area, you could have an index.php page that gets all the forms you need, and output it. Then, you'd need the included forms... which could be as easy as 1 file, with all the forms...
So, we've got the forms, and the index.... next would be the verification...
We need to set up some queries, and do some general checking, so it's a processing page, but of a different sort. We'd use a file (called verifiy.php) to get the login forms values, and check with the database values. If the user is verified, give a TRUE response, if not, FALSE. Then, we just load the proper page!!
And for processing, it's a matter of taking the form that was submitted... and then calling each function to either upload it, delete it, move it, rename it, or whatever....
Sounds easy enough right?
If you search the forums, you can find plenty of questions about image uploads & resizes. Then, it's just a matter of sitting down and coding it yourself.
I'm an advocate of learning by doing, rather than learning by getting. So I feel that you'd be better served if you at least tried to do this project. The main meat (displaying images) of the gallery is already done for you.
As far as implementing my tutorial/article, it's just a matter of you taking your site's layout, and then adding a table. That table would be the photogallery. There's really nothing to it. The only reason it may seem "odd" to implement is because I made it so broad so that anyone can use it.
~Brett