Sean recently made some big improvements to the JaxBoards software, including adding support for HTTPS. However, this upgrade had the side effect of breaking some images hosted off-site (as discussed here.

Yesterday I went into the theme files and replaced all images that weren't working properly. I've checked every skin, and I didn't find any issues. However, if you find any images that aren't working properly, please let me know so I can fix them.

I was still having some issues with the images, but it turns out Privacy Badger does some weird blocking with Dropbox? Once I tweaked its settings for that everything came in. Just a heads up in case anyone else is having a similar issue.