Drawing a blank here, but I can't find where the thumbnail sizes are set. I need thumbnails that are about 300px wide, not 100px. Can someone please point me in the right direction?

Depends on the theme which can decide to use the default sizes set on the theme options or override those with specific ones on the theme itself.

Well the theme options show it locked at 100 and it's grayed out, but in themeoptions.php, it shows this. So I'm still a bit confused as to where the 100 is defined.

setThemeOption('thumb_size',168,null,'zpmasonry');

It is greyed out because the theme sets it itself. So you have to look on the theme pages. We have a lot of functions to set the sizes on the layout which - as said - override any options. There are various layout reasons why you would want to do that, one would be responsive behavior which often works with columns so the sizes cannot be changed.

I still think there's something overriding the theme, unless I'm totally clueless (which very well could be the case). Everything in functions.php, themeoptions.php, and so on for zpMasonry shows the album thumbs should be more than 100px, yet on album view, I'm only getting 100px using:

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You have to look where the thumbs are printed. Which is mostly album.php for example. Sorry, again not familiar with the theme.

Right now it's litteraly the code I pasted above. Perhaps I need to look into printCustomSizedImage

This did the trick for me to get 280px wide thumbs. Thanks!
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