Great game, loved the gameplay mechanics (smoke, etc)...
I found it somewhat challenging a few times and had to check the YouTube (like the jumping one), but got through most of them, somehow even wondering HOW the heck I did it!
Only thing I was slightly disappointed with was the ending. In your first game, the turning point, the mental twist was in the death of his lover (Kathryn) as well as the meaning of the green box. That had a big impact and the idea to bring that character back and create a story around it was made perfectly, I found it very fitting and well made.
I liked how you switched to Jack's perspective at the end, but found the last two screens rather down-letting and would've loved if you played more with the "mental sting" (the part that gave you the chills).
He asking himself "did I meet anyone?" seemed rather unnatural and cheap. Also, Jack's character seems rather unsympathetic to me, like a lepricon of some sort.. but that's a personal view, can be dismissed.
Also, another point that could've played a HUGE role for us players would be the sudden appearance of the "green box" in the latter scenes of the game. It's an extremely powerful symbol that you could've used to enhance the emotional factor.
And finally a question - if Jack didn't remember who he met, how come he remembers it in Company of Myself? I'll assume these "drugs" influence short term memory ;).
Great game otherwise and hope you open a new series with similar gameplay, storytelling!
Respect to you Sirs!
Andi