When trying to change the "Thumbnails per page" field in the theme options control panel, I get some odd behavior.

Occasionally when modifying the value and clicking "Save", the number itself remains the same even when I get the green "Saved" confirmation - it's as if it doesn't 'stick' on the options screen for some reason.

On other occasions, the number is successfully changed on the options screen but in my album the thumbnails remain the same. I.e. I've set the value to "4" and am still getting 10 or 12 or whatever on each page. Anyone know the reason for that behavior? Is there a way to hard-code the exact number into my theme?

Depends on the theme you are using. Some have their own setting that override backend option values. Also if you use the static_html_cache plugin the display does not change until that is cleared and regenerated.

Also please search the documentation for the normalizeColumns() funciton

Thanks acrylian, normalizeColumns did the trick. I had been searching the functions guide for stuff related to thumbs per page, didn't think to do a search with the term 'columns'.

Well, we even have a troubleshooting entry linking to that function description because the question happens a lot..;-)