Missing files: What's wrong with these import/directory settings?

[btrcp2000]

I learned on the fly as I moved things over to Unraid, and apparently have some lingering issues with import paths I created along the way to a stable-ish setup. I have not been able to get my head around Linux filepaths and have no idea what the difference is between "var" "opt" "mnt" etc. I came from Windows, so my brain wants it to work like UNC. The files are visible on the shares via Win Explorer, so I am apparently not pointing the docker in the right direction.

In UNC-speak, here are the two paths I need:

\\UNRAID\sagemedia\tv
\\UNRAID\sagemedia\videos

Here is what shows in my docker settings

/opt/sagetv /mnt/user/appdata/sagetv/
/var/media /mnt/user/sagemedia/tv/
/var/mediaext /mnt/user/sagemedia/videos/
/unraid /mnt/user

Here is what Placeshifter shows for directories:

/var/media/tv
/var/media/videos

I know I will be facepalming, but what am I missing here?