I think you're misunderstanding (and it's probably my fault).
If I'm setting the directory where my recordings are when I set up my container, why am I getting prompted to set it up again when I log into channels-dvr via a web browser?
Shouldn't the container already know where I want my recordings kept?
Here's the page that I used to direct me on how to set the container up:
https://hub.docker.com/r/fancybits/channels-dvr
There's two directories:
/srv/dev-disk-by-uuid-c3811bd2-1ce1-44ea-b1e4-55f036ffeca1/MyDocuments/MyVideos/dvr - the config?
/srv/dev-disk-by-uuid-c3811bd2-1ce1-44ea-b1e4-55f036ffeca1/MyDocuments/MyVideos/dvr/TV - the recordings
I set these up in the docker config.
When I log into my newly created channels-dvr server, I get asked to pick a storage location. It does not let you pick a directory more than one level deep. And why do I need to set this again if I've already set it via the docker setup?
This is what the 'config' directory should look like for my installation correct?

And the recordings are here:

Those should be all I need right?