I duplicated the default theme and then trying to change the gallery's and album themes. In between my internet timed out and I could not change the theme of one of the album. When net restored, I again tried to change the theme, but it says for the album: empty $this->unique set is empty

I am using zenphoto version 1.2.5_RC2 [3991]

I also tried changing by editing the database table manually, but it is not working.

This is also happening for some more galleries too but not for all galleries.

I updated to zenphoto version 1.2.5_RC2 [4003] and problem is same.

This error occurs if you try to save an album which was not properly instantiated. Usually because there was some problem with the album name. We would need to know a bit more. Does this happen on standard themes?

This is happening on default theme.

What is different about the albums this happens for from those where it does not happen?

As such there is no similarities between the album where it happens but for the albums where I cannot make the change, change theme says Assign to the theme which I want them to change to.

On others, I can easily switch theme with no Assign button.

Ok, finally got it. I can reproduce this problem. Thanks for your patience.

The fix will be included in the 1.2.5 release happening some time today.