Hi David,
Can you post a sample file that returns 0000 for the frame 4 variable, {frame4}? Photo Mechanic will use the last 4 characters of the filename for the frame 4 variable, if the image file has the original name format. If the file has been renamed, then Photo Mechanic will look for the PM preference string in either the XMP or IPTC metadata sections. If the PM preference string is not present, then the frame 4 variable will return 0000.
Best regards,
--Bob