What you recommend?.
Yes, if you are camping in rocks and snow, you will want a footprint. Since there don't appear to be any specifically made for this tent, I suggest making one out of Tyvek. It is readily available at most home supply stores here in the states (not sure on your location).
Making the Tyvek match your tent dimensions perfectly is a touch of work. You'll have to set up your tent, trace out the pattern, cut, and grommet.
What I am doing is to set up my tent on a large rectangle of Tyvek. I then mark a pole and set a grommet. I put the tent pole through the tent grommet and the Tyvek grommet. Then I do the grommets to the left and right of the first. Next I do the grommet opposite. Each time I make sure the Tyvek is taught before marking and setting the grommets.
Lastly, with the tent up, and the poles fully set through my Tyvek, I mark where to cut for my footprint.
If you are concerned with strength, reinforced grommet areas with a strip of Tyvek tape.
Yes, I would highly recomend a footprint. There are a lot of pros.
You can use a piece of plastic as footprint. In the snow it's really nice to use a rescue blanket, they reflect the heat.