Docker snap installed, but not showing up in the Container Engine app

Hi, I've got a snap docker snap installed on a virtual-ctrlx-core (amd64)

I followed the example here described here by Sgilk  https://github.com/S-Gilk/ctrlX-Docker-Ignition

ctrlx-docker-ignition seems to be installed on "my virtual-ctrlx-core", but :

• localhost:9088 doesn't return anything in the web browser
• and the app is not showing up in the Container Engine app

port forwarding is enabled :

• on ctrlX virtual settings in CtrlxWorks
• and on ctrlX CORE network adapter to access the webserver externally
   

Any idea ? 
Thanks in advance