The last few shows I have added are not being picked up when I run a library scan. I added season 6 of Wild America (it picked up the first 5 seasons just fine) and the entire show The New Adventures of Brisco County, Jr. are not found. I am not sure if I did the log files correctly or not.
My guess is that you haven’t changed the security access for the user plex on your synology. This happened since the last release. See the following article.