Have you carefully put a screwdrive blade in through the port, and pushed the outer surface of the ring toward the piston? The issue is whether the ring is stuck in the groove, or is capable of moving a tiny amount radially. The rings can become stuck in carbon so they won't move - when that happens they will not seal, and combustion gases blast past them, eroding the bore, the rings and the piston ("blow by"). If the rings are actually stuck, you need to remove the piston, remove the rings from it, clean the ring grooves, and almost certainly, fit new rings. I can't tell from the pictures whether your rings are stuck.
A bit of mild scoring on the upper part of the piston between the ring grooves is not of much importance, as long as the body of the piston and the bore are not scored.
