In order to get the docker images of your application, the IE App Publisher needs to access the docker engine via the Engine API. By default, the Engine API listens only at a UNIX socket, so we have to bind it to a TCP socket at the host.
Follow these steps to enable external connections to your docker engine:
sudo systemctl edit docker.service
[Service] ExecStart= ExecStart=/usr/bin/dockerd -H fd:// -H tcp://127.0.0.1:2375
sudo systemctl daemon-reload
sudo systemctl restart docker.service
sudo docker info
The output should state that the API is accessible on your IP and Port.