I found more about the error. The post processing failed at:
"%relpath%\software\AutoImager\AutoImager.exe" /f %relpath%\temp\stage5\%page% /p Dilate /d /op %relpath%\temp\stage6\
I tried to run this command manually using some of your output images. It didn't produce any output files. This is probably why I got blank images at the end. Is there any reason the AutoImager doesn't work?