The developers of that demo simply did not
develop it for a casual game audience..
Used too many expensive effects.
(basically they suck)
I wonder how the framerate is, without these effects..

Some small recent games of mine:
Griefer 4k http://damocles11.byethost9.com/griefer4k.html
Kobold 4k http://damocles11.byethost9.com/kobold.html
Cave 4k http://damocles11.byethost9.com/cave4k.html