thank you for the interesting explanation and thank you for the download instruction above.
the disconnected computer is in an area without internet and mobile connections so I have to use my smartphone to take the software and then put it on the computer…I hope this is momentary.
I didn’t know anything about the connections to other snap. my last information about this was that snaps come with all libraries included so no more external dependence 
so, if I understand correctly what you said, snapd tell the snapstore my computer configuration and installed snaps and through this is generated an assertion file that tell my snapd what else snaps are needed and how to install them, is it right?
why the instructions about the interfaces needed by the snap don’t come inside the snap itself and need a communication with my snapd ?