The gold/brass looking piece (valve guide) goes on the front part of the cupseal (black part) Then put that little spring on top of the cupseal with the valve guide in between. (smaller end of the spring attaches to the cupseal) Put the valve back in (silver thing with the orings) There should be a big opening and small opening on the valve, the little opening needs to be facing the rear of the gun and the big opening towards the front. It goes in the lower tube on the gun. Use a pen or pencil to push it back in. That little gold screw holds the valve in place. (The screw goes on the under side of the gun, where the grip frame attaches.) Push the whole cupseal , valve guide and spring back into the front lower tube of the gun.( The silver part of the cupseal will go in the valve opening) Your pictures are missing one part, the lower pressure chamber, that screws on to the front lower tube of the gun after all those parts are on.
If that doesnt help look at this, its basically the same parts as the piranha