saving progress (also spoilers)

[Спартак здесь?]

so, I've hit my first antichamber run, and it turns out I need more steps and my layout was wrong (cant do anything in reservoir). so question is, do I need to hit antichamber again on my next run, or basement door will be open? is there a way to save progress from where I am now (or further down the line), or I am starting from scratch no matter what?

[Gorlom[Swe]]

if you got to the door and used the key that specific basement door will persist as unlocked.