Seems like I am experiencing the same thing.

I tried image-store v3.2.0 and was able to upload images to galleries and create albums. Image files created were confirmed by looking through FTP.

When I create a page with a short code such as [image-store] all the thumbnails images are broken.

I have tried enabling permissions to 777

I have enabled image hotlinking on the server

I think the issue lies with image.php

P.S. the above link doesn’t work.

Hope you can clear up this issue, the plugin is awesome.