I was having issues getting this up and running on my Synology DS1019+; mainly because I only have a rudimentary understanding of Linux. So if there is anyone else in the same boat, I found these two links to be helpful:
Creating custom "TV channel" streams on Plex using dizqueTV
How to login to DSM with root permission via SSH/Telnet
So, I was able to get it installed and working...mostly.
In Plex, the 24/7 custom channels I created are there, the guide data is there, and it plays as intended. But, in Channels DVR, I loaded the m3u file (which it does direct to the xml file with the EPG data) and it shows and plays the 24/7 custom channels, but there is no guide data for the episodes. Any suggestions where to look to get the guide data into Channels DVR for the custom channels?
EDIT: I found my problem. The location to specify the url for the xml file was a bit hidden: