I added FlA Gallery to a WordPress site that has 2 blogs as part of the same domain. For the first domain, I was able to successfully add a gallery and associated galleries.
For the second blog, I cannot add a gallery. Here are the steps I followed:
In the dashboard, I go to FlA Gallery -> Manage Galleries. Then I type in a name for a new gallery and click "Add Gallery". When I do this, the page reloads and no new gallery appears in a list of galleries (and there are still no galleries). In the first blog, the same steps create a gallery.