Let's hope this makes some sense about password protecting a gallery or individual albums. This is information I got from Yahoo (my small business web host). To password my gallery or albums I would need to do this:
1) Create a folder on the server names SSL.
2) Upload my gallery into that folder. Shozam builds subfolders inside the gallery (my gallery name is gallery which also builds the folder named gallery. It also builds subfolders 1, 2, 3, etc for each individual album.
3) To control which albums I can password, supposedly I can pick any folder or subfolder inside the SSL folder and password protect it. I do not have to password all of them or even the SSL folder. So therefore I could password protect gallery/1 or gallery/2 or whatever I choose.
4) This is only an assumption on my part but I believe Yahoo uses Apache server and I assume most web hosts use the same. I would imagine most are set up about the same. Razvan could probably be more detailed about this.
I have tried using some other scripts, cgi etc to password parts of previous websites but found that most lacked some strong security, ie, right click on the page in your browser and choose page source. Bingo, LOGIN AND PASSWORD. If the webpage uses frames it is a bit harder to find the login/password.
Hope this helps and I'm not too far off base with this one.