I would certainly NOT trust it to tape, and if you are not allowed to put any holes in the wall at all, then the only thing you might want to try is hanging the mirror using an over-the-door hook, something like this:
0_1502199732610_22461740469584p.jpeg
You should be able to find something similar, and likely more apt at a local hardware store.
Otherwise I’d recommend just leaning it against the wall and don’t bother hanging it until you move to a permanent home.
@oldversions You may have better luck asking this question in another forum like Retropie.
While the standard Retropie setup is a full SD image, I’m sure someone there can lead you in the right direction of installing just the emulators you want without the whole front end.
Also take a look at RetroArch. It creates a minimal front end for many emulators, including NES/SNES. You can pick and choose what emulators you want so you don;t need the whole gamut just to play NES/SNES games.
