How do i setup UPnP / port forwarding?

[lichtblick 0]

Hi i have a server at home and want my employees to access it via UPnP
 

(it must be UPnP. My server is basically a windows laptop and i have a windows app running there (for a specific use case, its called Laixi) and it tells me to use UPnP)
 

my server doesnt have a public ipv4 and i dont wanna ask my provider (because i am in an asian country rn)
 

So i bought AirVPN. How do i set this up now? i heard i need to enable Port Forwarding? or do my employees need to login into AirVPN as well? sorry i am a noob

I enabled one Port at the website but i run into errors
 

Can someone help me how to setup this stuff? I need to make it possible for my employees to access my server via UPnP


my laixi error message (the reason why i bought now airvpn)

Edited ... by lichtblick

[Stalinium 49]

Hello. AirVPN's routing servers do not support UPnP. Instead the configuration of ports is completely static, it's what you see in the client area. If you really have no way to tell this local server application to use another port, then it won't work well with AirVPN. As an alternative you may want to try out "mesh" VPNs that interconnect different computers such as Tailscale, the Yggdrasil mesh network; or services that allow outside connections to reach you like ngrok.

In AirVPN's port-forwarding configuration, the big 62xxx number is what you would give to your colleagues (aka public_port). For example: CURRENT_EXIT_IP:public_port. Or if you added a DDNS name, you would give them: my-name.airdns.org:public_port (provided you only have 1 connection with this port-forwarding and name).
The local port is what's configured on your local machine. For example, if the server app tells you the port it's listening on for connections, you could do the following:

1. Start server application
2. Write down its port aka local_port (its network socket must be opened on 0.0.0.0:local_port)
3. Go to AirVPN port-forwarding
4. Keep big port number the same (public_port)
5. On AirVPN change small "local port" to application's "local_port"
6. Connect to AirVPN
7. It should be forwarding my-name.airdns.org:public_port -> your_computer:local_port now.

Make sure device's own firewall does not interfere (Windows Firewall usually causes problems)

What I personally don't understand, if the port-forwarding configuration applies in real time to existing connections or not. How long does it take to save the new setting if you are not yet connected? Although the way I described it above should be safe and always working.

PS: I am just an AirVPN user.