Love the aesthetic, the pixel art and palette are downright gorgeous. In terms of gameplay, I enjoyed trying to solve a winnable strategy for each level. Originally, I had tried to keep 4 segments open at all times, swapping between them as needed, but this often led to a prisoner escaping with seconds remaining, which set me back.
Eventually, I found my most consistent strategy was to open as many walls early as to drop the ventilation, before going on the defensive on the latter half of the progress meter. Experimenting with different level layouts kept each run enticing, as I'd have to consistently think on my feet.
Overall, I'd like a bit of leniency introduced to the game, rather than the all-or-nothing win condition that is currently being employed.
All together great work!