Files are uploading successfully (can be seen in ppom_files folder on the server) but immediately after upload we get an error 200 in the browser. I am assuming this is when it tries to generate the thumbs, as they are not being created.
All php settings are to max on the server.
Does PPOM use GD to resize for the thumbnails, or Imagick, or something else? Could there be a limit in there somewhere that stops the thumbs being generated? Just a thought.