Looks like Gallery2 is getting obsolete. Actually WPG2 plugin is getting out of date and sometimes pain to work with, as it was not updated in long time and has definite compatibility issues with WordPress 2.7. And, frankly, Gallery2 is way too slow, though it’s one of the most flexible and powerful gallery scripts out there. It’s time to try out alternatives. Here’s a good start point, post about gallery plugins for WordPress:
What do you think?