Umb 7.5.11, PdfThumbnail 0.9.9

When uploading or just re-saving a PDF I get a full copy of the original PDF with a generated file name instead of a thumbnail image generating. Every time a page is called another full copy is created.

The PDF used for this particular example has been used in another site where it generated thumbnails perfectly.

Trace log:

00:22:52.067    ERROR   MissingCode.Umbraco.PdfThumbnail.ThumbnailGenerator 
Faled generat pdf thumbnail System.BadImageFormatException: An attempt was made to load a program with an incorrect format. (Exception from HRESULT: 0x8007000B) at GhostscriptSharp.GhostscriptWrapp
00:22:52.067    INFO    MissingCode.Umbraco.PdfThumbnail.ThumbnailGenerator 
Completed Creating Thumbnail (took 16ms)
00:22:52.050    INFO    MissingCode.Umbraco.PdfThumbnail.ThumbnailGenerator 
Started Creatning Thumbnail
00:22:52.037    ERROR   MissingCode.Umbraco.PdfThumbnail.ThumbnailGenerator 
Faled generat pdf thumbnail System.BadImageFormatException: An attempt was made to load a program with an incorrect format. (Exception from HRESULT: 0x8007000B) at GhostscriptSharp.GhostscriptWrapp
00:22:52.037    INFO    MissingCode.Umbraco.PdfThumbnail.ThumbnailGenerator 
Completed Creating Thumbnail (took 80ms)
00:22:51.957    INFO    MissingCode.Umbraco.PdfThumbnail.ThumbnailGenerator 
Started Creatning Thumbnail

Any clues to get this working reliably would be appreciated.

--Craig