its not selling cause it sux ass - simple. yes its a unique concept, but its not fun to play.
if you want to make a game that sells, do some market research... and then follow up with a game that is actually good and fun to play.
the penumbra games were OK but they had a bad case of amature dev's. and this is basically the same thing.
all you seem to do is wonder around in the dark avoiding enemies, then you touch something and rotate an object, read a note or 2 and then repeat.
something that would make it sell would be to allow your character to actually kill stuff, make it co-op so you could solve puzzles with 4 players and increase the interactivity of all of the objects so that the 4 players can interact together using different objects to achieve a shared goal - e.g. player 1 has a rope, player 2 has a hook, player has a welder to weld hook and rope together, player 4 has a spear to throw the hooked rope up somewhere - everyone climbs out- puzzle 1 solved.
also there is tension, and OMFG my character is a useless gimp that can't do anything- its soooooo frustrating.
actually frustrating is the word i would use the describe all of their games.
"Money doesn't exist in the 24th century, the acquisition of wealth is no longer the driving force in our lives. We work to better ourselves and the rest of humanity." - Jean-Luc Picard