You do know this game was made over a year ago? The Heist 2 is already out and learns from all those tidbits in this game. The Heist is still a great game and runs pretty well on low-end machines regardless of what your comments are.
Play to the end, the experience gets stronger, you have to earn it.
As for the sticky key issue, if it's Internet Explorer and a ton of other games simply update your browser to something like Mozilla Firefox and a later flash player from Adobe. Not difficult and 100% free to do.
Just thought I'd clear some stuff up, there is a pause button (Press Esc), you can mute the game sounds (it's in the pause menu), toggle quality with Q if your computer is struggling. Most importantly — the smoke disappears when your framerate drops below a certain amount to make the game remain playable on slower machines/browsers.