We didn’t bother with adhesive in our T6 camper. The Altro is held in place on the drivers side by the furniture, at the back by the bed and the rear threshold, at the front by a carpet strip, and on the passenger side by the side door step.
No signs of it moving or rippling at all.
Gluing it might be the best overall solution, but I was worried about positioning the Altro incorrectly, and not being able to move it, or tearing it in doing so.
Pete