It appears that Photo Mechanic ignores large files (greater than 4GB) and won't include them in a contact sheet.
When I look at my contact sheet, video files larger than around 4GB are missing. It's not that the thumbnail preview is blank, it's as if the file didn't exist at all.
The files get ingested and renamed properly off the memory card, but don't show up in the contact sheet, nor do they get an associated sidecar file with the ingest applied IPTC info.
The file itself seems to be fine, and QuickTime Player is happy to play the file.
For instance, I have a folder with the files:
20180915-117.mov 8.4MB
20180915-117.xmp 2 KB
20180915-118.mov 23.9 MB
20180915-118.xmp 2 KB
20180915-119.mov 6.06 GB
20180915-120.mov 4.18 GB
20180915-120.xmp 2KB
20180915-121.cr2 35.8 MB
20180915-121.jpg 7.6 MB
20180915-121.xmp 2KB
20180915-122.cr2 35.4 MB
20180915-122.jpg 6 MB
The contact sheet skips 20180915-119 and goes from 20180915-118 to 20180915-120.
I'm running Photo Mechanic Version 5.0, build 19695 (4a8c3fe) on a Mac with OS-X 10.13.6 (17G2307) (Primary drive is an APFS SSD). I have selected "Unknown files as proxies" under the View menu.
My recollection is that Photo Mechanic has been doing this for awhile. I believe I have seen this same bug with earlier versions of Photo Mechanic and earlier versions OS-X with HFS+ file systems.
Is this a know bug? Is this something that can be fixed in a future update?