Question - mp4 thumbnail icons

WD Software & Mobile Apps My Cloud 3rd Party & Mobile Apps
2

None of the files that existed on your drive before that firmware update will ever get an icon, unless you trick the NAS into thinking the file has been updated.

You could try this:

http://community.wd.com/t5/WD-My-Cloud/HOW-TO-Get-Video-Thumbnails-on-My-Cloud-app/m-p/657625#M4539