Here are all the shortcuts from Kitty: Isolation Redux mod compared to the Alien Isolation vanilla game (all the time saves listed are approximate):

M1: 2:40 - You can run directly to Verlaine which ends the mission automatically

M2: 14:50 - Entire mission is skipped

M3: 0:58 - Flight Recorder cutscene is skipped + Hack door to security room is open

M4: 0:46 - Hughes's cutscene death is skipped + Exit tram is faster

M5: 0:40 - Kuhlman's dialogue is shortened + Tram entry is faster

M6: 0:50 - Explosion cutscene no longer happens (door to exit is unlocked)

M7: 0:07 - Compression Cylinder Elevator is faster

M8: 2:40 - Elevator to Transit Control is already opened + Exit tram arrives faster + The arrival at Solomons is skipped

M9: 10:50 - Entire mission is skipped

M10: 1:06 - Waits dialogue is shortened near the start + Tram to Systech Spire is faster + Ricardo opens Server Hub exit faster

M11: 1:25 - Entry torch panel door is opened + Robot vent is opened + Ricardo's dialogue is shorter + Exit tram arrives faster

M12: 0:45 -Torch panel/code door in Seegson Synthetics is unlocked + Tram and elevator are faster

M13: 1:00 - Tram entry is faster + Code door is opened + Apollo's vent hack isn’t required

M14: 1:20 - Elevators move faster + The reactor purge sequence is skipped + Exit tram arrives faster

M15: 7:30 - Anesidora is skipped entirely

M16: 9:30 - Doors at the beginning are already open + The door near Ricardo is open immediately + Spacewalk is skipped

M17: 0:14 - Canteen forklift blockade rises slightly faster + Tram from the first area is faster

M18: 1:00 - Hazardous trams are removed + You can run during the spacewalk

M19: 0:05 - You can run to the QTE event

Total: approximately 58:16 faster than vanilla

NOTE: For all shortened dialogue you must be playing with English audio.