Known codes for the safe:

if M (last number "x" could be any; often 0, 3, 6, 9; rarely 8, 4, 1; never 5, 7, 2):

0 then

1 then 69113x

2 then 70224x

3 then

4 then 92446x

5 then 03557x or 41559x

6 then

7 then 48773x or 41773x

8 then 38885x or 30886x

9 then

Important timings:

Starting point early Class Room: ~2s to code room (~4s in total back and forth)

Starting point to Day Room: ~15s Exit to Day Room, ~12s Left to Day Room

Day Room to Science Lab: ~18s Exit to Science Lab, ~16s Right to Science Lab

Science Lab to Courtyard: ~16s Exit to Courtyard, ~17s Straight to Courtyard (meaning Straight is faster, cause that saves ~3s, thanks to the late code room)

Locker Room to Iss Room: ~21s Left to Iss Room, ~17s Right to Iss Room

Taking a door takes 4s IGT.

Texts, typing codes, computer, cutscenes, pause do freeze IGT, meaning they do NOT count towards result screen's time.

This list is for important timings on avoiding the monster assuming optimal movement and stamina management.