Moodle stores information students enter in a database and has some features to make sure nothing dangerous gets added to the database.
PhotoFrame does not use a database. It stores information in text files, so you can use it on a server with no database attached. Of course PhotoFrame already has some security features attached, but integrating it into a larger apllication demands some more thinking about security (think about redirecting other students to a fake login page, etc... such things are not possible inside the original PhotoFrame because this didn't use a login page...) I can't predict what could go wrong.
Unfortunately, further integrating PhotoFrame in Moodle would mean rewriting almost all of the code. It's not a matter of fixing some bugs. As I am no longer using the module myself, it is kind of low on my to do list. Sorry to have posted a first version and then abandoned it. Because of lack of server space for the pictures, and beause student comments proved too be to hard to moderate, our school is now hosting the picture gallery on a simple and cheaper (no php) webspace.
The datamodule will provide ability to upload pictures with metadata attached to them.