Hi Backer,
You need to use file upload then you can access in action where you get binary data and filename from the file upload. Just save the image in some folder then save title, description and image path in the database.
Now, on the screen where you want image gallery to display just get all records from the database and bind the record list with the image gallery component. It will work and display your image gallery.
Regards
Rajat Agrawal