Are you referring to the Gallery module?: http://moodle.org/mod/data/view.php?d=13&rid=89
This doesn't link with Glossary module in Moodle.
It allows a Gallery2 installation (a separate programme to Moodle) to link with Moodle.
So for example in Moodle you could create a new 'Gallery' in your course (which is actually linked automatically to the Gallery2 installation).
A few months ago I setup Gallery2 (a reasonably easy process - quite similar to a Moodle installation) but could not get the function within Moodle to work
It seems there are a number of problems to resolve to make it work.
There are some discussion about how it works (and how some problems can be solved) here:
http://moodle.org/mod/forum/discuss.php?d=42459