this is from the sites help page
“I recieve a Runtime Error 500 - unknown image error at line 657 error”
Make sure your Textures and Templates folders are present in the same folder as the Entity Workshop application file.
Make sure you have specified your correct FPS Creator directory location upon Entity Workshop’s first start up. The location of which should appear on the first line of your “Config.ini” file.
It has also been reported that Windows Vista users will need administrator privileges in order to run Entity Workshop, otherwise similar error messages may occur.
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