New server and client help

[Magg66]

So:

Ubuntu OS
Mergerfs
Docker:
-portainer
-jellyfin
-gluetun
{apps we don't discuss - TDP}

Issue right now is with gluetun and {apps we don't discuss - TDP}. Gluetun is working, checked logs and ip leak. {apps we don't discuss - TDP} is using gluetun for connection that works in a way.
It’s {activities we don't talk about - TDP} probably problems with port forwarding. 
The other issue is can’t save files on mergerfs mnt. When I’ve changed downloads file location it downloaded (??) but the file doesn’t exist. Can’t find it anywhere. 
That right now is the issue I’m having. Not sure if it’s because of mergerfs or gluetun and vpn. 
Might be that I took bit too much for the first media server. Never used linux for a long time, and forgot everything I knew about it. So I’m learning as I go. But the thing is I would like to have “normal” os so I can use some other programs. 
Not really sure what to do now. 

Remind me what the issue was that started us down this path?

Describe the current state of your setup again and the problems you are having.