All warnings of running beta software acknowledged...
I've found that running the DVR on Catalina using an external drive breaks the current update mechanisms.
Essentially, in Catalina applications require explicit user approval to access external drives. Supposedly, a user only has to grant this access once and MacOS is supposed to 'remember' the access granted.
What I am seeing is that each upgrade of the DVR software (ie; beta version in this case) requires user approval and creates a new approval entry in the Files and Folders section of Privacy within Security & Privacy settings.
I suspect this behavior is because of the linking of the latest version rather than running an explicit binary for channels-dvr.
At this point, I don't know if this behavior is permanent but I am suspicious that it might be so thought I'd call it out.