Looking around some more I found a spec for the exported files. I grabbed some code to read png from libpng documentation and coded up a quick importer. With that I tried Super Mario Bros which turned out to be the music not a game. Then I tried Space Invaders, Into the Dungeon We Go, Frogger, Undertale, Turtle's Adventure. Into the Dungeon We Go did not import properly. Still need to look at that. Frogger imported but got stuck when playing. Maybe it has a bug or an update to Redshift broke it. The other three played fine. They aren't as good as I'd hoped but maybe the platform is too limited for much more.
I plan to make the importer easier to use. After that I keep thinking of creating my own redshift player. Maybe enhance it to be a better development platform but we will see.