Just an FYI - If you are running Channels DVR on a Synology NAS directly, avoid upgrading to the DSM7 preview. I wasn't paying attention and didn't realize they block all 3rd party packages. Running in docker works but you'll lose hardware acceleration. Downgrading back to 6.2 was a major PIA.
Also, a note to the Channels devs, you might be aware but synology is changing their 3rd party SPK format and permission structure with DSM 7. Hopefully we can maintain a native spk when DSM7 comes out of preview. I got a warning when trying to install it about the privileges issue (I'm assuming you use root) but it could have also just been the default message for all 3rd party packages.
Best info I could find here. They seem to be limited in their dev documentation so far: