These screens are known by many, what Im saying is that with only screen you can't make the exact same game, simply because it only shows a fraction of screen, not even a entire one. But yeah, they are really good and shows how its possible to do amazing things with a low amount of colors.
I'm not saying its impossible to do something inspired by these images, but doing things that aren't shown and still having Optomon acknowledging it as the same game is. It would be the same thing of using Bloodlines zeppeliin stage's screenshot alone to recreate an entire area that we don't know the design, show it to some Konami employee that worked at it and they say "Wow, its the same thing"
Probability nears 0, so I think without being in touch with Optomon or Thaddeus (or having more data) its not possible to do the exact same thing, but something similar is totally possible.
Off: Its good to see this thead being so lively.