print portal problem between https and http Follow

Hi, I've a issue with print portal major version 8.

I've correctly install it, create a certificate for publish in https and setup inside the print portal for work in https and when I browse through the folder that have the labels works fine. I see correct the preview but when I choose from a label "print preview" or "print" the following visualization show in http mode, so in extranet the firewall cut the http connection.

Is missing some configuration that the printportal open the previous interaction form in http?

Thanks, Daniele.