I installed Gallery2 for one of my clients. I then integrated Gallery2 with WordPress using this plugin.
Everything seemed to go fine except I could not get Gallery2’s URL rewrite to play nicely with the WordPress installation which resulted in thumbnail images not showing up in the sidebar. After much experimentation I finally decided just to turn off Gallery2’s URL rewrite to resolve the problem. I tried using this help page but it didn’t work for me.
I am also unsure how to make the Gallery2 pages look more integrated with the WordPress pages. Right now it’s glaringly obvious that the Gallery2 pages are not part of the rest of the site.
Gallery2 is pretty cool. It is quite improved from the original Gallery. I like how you can set the permissions for individual photos so that certain photos only registered users can see. It was annoying though that I had to type in the group name “Registered Users” instead of being given a choice in a drop down list of which group I want to assign a new permission.