Problems with the Project Page and the Portfolio Element

I have a problem with the Project page when I try to add the Portfolio element of the theme. I have disabled the Projects Navigation and the Related Projects from the Theme Settings because I prefer add the Portfolio theme element directly on the Project page and configure a custom display for the other projects. But when I try this option, everything disappears on the page and I can’t see the content.

Is The portfolio theme element incompatible with the project page?

Thanks!
Best Regards