I think I have finally fixed the instance of Gallery2 on my web site for real. I am now able to add new images and do pretty much everything with it I did before. I wrote about how I broke Gallery2 here. Since then, I fixed it, but incompletely: it did not allow me to add new pictures. After some more work, I solved that last remaining glitch. What was wrong the first time? The short answer: I had overlooked a table that contains a column that is (I think but am not completely sure) auto-incremented each time a new item is added to Gallery2. That column generates unique IDs for Gallery2 items. Since I did not set its value to the value of the latest item inserted before the upgrade, it was generating ID values that were already "taken" by older items. The full, updated story of how the brokenness came to be and how I fixed it, is here, and yes, I realize that none of the handful of readers of this blog are interested in either the problem or its solution. :-) I'm posting the link here purely "for the sake of completeness", as they say in mathematics. :-)
I also need to find a way to put StatCounter code on my Gallery2 site. It's not obvious where in the Gallery2 bowels its HTML is generated.
However, I am not sure if I want to continue to use Gallery2 at all, or if I want to switch to a different software. My ideal software would have the features of both a photo gallery and a photo blog. (I wrote more about features I look for in photo gallery / blogging software in this blog post.) I tried out two systems that claimed to have such features, Cheesecake Photoblog and Sylverblog, and they both were pathetically unusable. They were so bad I'm not even motivated to write about all the ways they are bad. :-)