Captive Portal didn’t work for remote Networks

[Andiii]

Hello all

I have a fresh install of OpenSense Version 1.8.1.4 and we would like to give our guest internet access from all our company location.
But we need a splash page to accept our AGBs.
We have different location and on each location we have a WLAN SSID with a separated Network.
This Network did we routing to our Datacenter and there we have install the OpenSense Proxy and a separated DNS and DHCP.

The Proxy Server is only for free internet to our guests.
The Traffic from our LAN-Network is separated and has his own Firewall, so that can't reach the Proxy. The WLAN Network Use VPN Tunnels to reach the Datacenter (provided by our Firewall).

So if I setup the Captive Portal according your documentation, it didn't work.
If I deactivate the the Rule to "Deny Traffic" direct to the Proxy then I get Internet Access but without "Splash Page".
The Inside Interface on the Proxy has 10.4.4.4 so if I put a Device in this Network and test it, the "Splash Page" will work, still with active Deny Rule.
But if we came from the remote Network 10.16.0.0 over the LAN-Port 10.4.4.4 then it didn't work.

Please help us, because at the moment we can't use OpenSense and cant provide free Internet without the "Splash Page"

Thank you very much.

[Andiii]

Can nobody help use ?  :'(