Ah, I see.
Any plans to expand upon it now that the Jam is finished? ^_^
The problem with the mc's past isn't the vagueness, so much as the fact it's being referred to several times.
The mc have feelings and mementos of their past. It crops up here and there again and again.
Like the Chekov's gun concept says; If there's a gun on the wall in act 1, it should be fired in act 3.
It creates an expectation in the reader that it will be revealed --especially with a game that has the atmosphere of mystery.
If the past did not matter, then it shouldn't be hinted at. OR it should be an open choice at the beginning; A.i:
"I ran away because..... a) debt, b) I killed someone c)...." you get my point.
Ah, I see. I must have missed the place where Modesto saw the mc perusing the book. lol
And considering how good your story is, especially if you choose to polish it, that is sad.
I think you might have earned it cost back plenty.
But I will concede that it would help if the game was longer.
(Then again, a game that somehow got good reviews on Steam is a game in which you are a rock.
You cannot move, or pain the rock. You just....sit there. As a rock. That's the whole game. o_O
So my point is; People buy shitty games, and your game is a million times better than a game in which you are a rock.)