RDPGW not transfering data to remote Host

[NalertN]

Hello,
I have completed the Configuration of the RDPGW for local authentication

I now run into problems when connecting to a remote Host behind the Gateway. When I try using the Gateway in mstsc.exe it gives me the error:

In the firewall behind the RD Gateway I dont see any traffic.

Is it correct that I only use the Username/Password for the Remote Computer and not for the RD Gateway e.g. root?

How does the RD Gateway know where to send the traffic? Does it do a DNS Query and the send to the forwarder Adress/Gateway Address?

My Docker Compose file with change IP adresses:

version: '3.4'

services:
  xrdp:
    container_name: xrdp
    hostname: xrdp
    image: satishweb/xrdp:latest
    ports:
      - 3389:3389
    restart: on-failure
    volumes:
      - ./xrdp_users.txt:/root/createusers.txt
    environment:
      TZ: "Europe/Amsterdam"
  rdpgw:
    container_name: rdpgw
    hostname: rdpgw
    image: bolkedebruin/rdpgw:latest
    build: .
    ports:
      - 8080:8080
    restart: on-failure
    volumes:
      - ./xrdp_users.txt:/root/createusers.txt
      - ./rdpgw.yaml:/opt/rdpgw/rdpgw.yaml
      - /opt/rdpgw/server.pem:/opt/rdpgw/server.pem
      - /opt/rdpgw/key.pem:/opt/rdpgw/key.pem
      - /opt/rdpgw/server.csr:/opt/rdpgw/server.csr
    environment:
      RDPGW_SERVER__SESSION_STORE: file
      RDPGW_SERVER__CERT_FILE: /opt/rdpgw/server.pem
      RDPGW_SERVER__KEY_FILE: /opt/rdpgw/key.pem
      RDPGW_SERVER__GATEWAY_ADDRESS: 192.178.1.1:8080
      RDPGW_SERVER__PORT: 8080
      RDPGW_SERVER__HOSTS: xrdp:3389
      RDPGW_SERVER__ROUND_ROBIN: "false"
      RDPGW_SERVER__AUTHENTICATION: local
      RDPGW_CAPS__TOKEN_AUTH: "false"
    healthcheck:
      test: ["CMD", "curl", "-f", "https://192.178.1.1:8080/"]
      interval: 10s
      timeout: 10s
      retries: 10

Do you maybe have any cues how to get further or how to troubleshoot?