So, I went to look at the demos, and (since I'm not much of an arcade gamer) I clicked "Isometric test". I figured out how to scroll around and delete blocks, but I couldn't seem to create them - somewhat nihilistic.

Then I went to "Elevator Action", hoping I could figure out how it worked. No instructions, but the arrows move left and right; up jumps, and space fires. Fair enough. There's four levels of doorway, and only one platform to walk on; there's a ceiling light floating in the elevator shaft, I can walk into the elevator when the floor is waist-high, and be gently deposited at the bottom of the screen (until I move, then I fall to an untimely death). I can't open any doors, and walking off the right-hand-side of the screen does not make it scroll.

I realise that these are just very basic demonstrations, and that your library is probably much more versatile and impressive than these small demos indicate, but the first impression I got was pretty soul-crushing.

The "Biolab Disaster" game that serves as ImpactJS's demo is a pretty poor game in that it doesn't have any particularly novel mechanics or level-design or interesting systems to manipulate, but it is technically awesome, with great graphics and music and animation, and really shows off what the library lets you do.

EDIT: If your demo game is hurting from lack of artwork, free game graphics are not hard to come by: http://www.lostgarden.com/search/label/free%20game%20graphic...