First things:
Under the thumbnail for each gallery, click on the "settings" link. In that next page, under "Security & Privacy", click on "no" for external links, "yes" for protected, and limit the size to Large or eXtra Large.
Next, come up with a watermark. You should have a hidden gallery somewhere (click "unlisted") and you can use it for odds and ends like the graphics that you need for watermark. (You probably already have this, but naturally I can't tell.) Create something in photoshop that has the information you want â name and email, for example - and save it as a .PNG file with a transparent background. (You'll probably need to experiment with the size of the lettering and the size of the blank transparent canvas to get one you like, so expect to make many of these.) Select one of these in that gallery, click on 'tools', and select 'make into watermark'. (It's a little buried.) Then you get to change where it's placed and its opacity.
And you can change your watermark and apply the new one to an entire gallery at any time, and as often as you want to. So there's no need to get it perfect the first time.
You can also clone settings from one gallery to the other â I've never actually bothered, but I heard it's possible â so if you set up one, the rest are easy.
But: it looks good. I've only done a quick inspection so far, but I like what I see.