Yes, it was resolved, but only after quite a bit of back-and-forth and a replacement file.
Check that Safe Mode is OFF. As I was first using WA File Manager to upload an image file, I had an issue with my server assigning the wrong "user" to the file, so maybe check that too.
As I was using an include file I also needed to change the code inside the include file to:
echo(getCachedResizedImageHTML(ob_get_clean(), abs2rel(rel2abs("../image_cache", dirname(__FILE__)), dirname($_SERVER['PHP_SELF'])), "proportion", "", false));
The file I was given to replace was "CachedResize_Image.php". I guess you'll need to ask Support for it.
This is in no way a solution to the issue as there are many variables, however hopefully it will get you started on finding a fix.