The NS2 system was based on the glock system they developed.
IIR there are quite a few threads about it on the KWA forums.
The ATP is just a glock (even fits in glock serpas), but because KWA got aswhooped by glock over the patents so they've just renamed it and gave it a slightly different look.
while that is Correct that Glock's were released Pre NS2 they NOW all run on the NS2 and were made to before the rest of the Pistol's came out. EG
Same Design in the Pistol's just a few part's were changed like the air nozzle was changed ever so slightly but it increased performance! also the changed how they finished the paint on the metal bit's and bob's (Not too sure if i find it annoyingly good or bad).
i geuss in a way we are both right but i'm right deal with it