Pressurisation Problem with new half sliding door (with steps to repeat)

Here is my test space vehicle (blueprint, Steam Workshop).

Paste the vehicle into a vacuum environment (such as space). You might need to spawn some ice into any inventory for a consistent O2 supply.

At the front of the vehicle is a simple airlock with two doors. Starting from within the with all doors closed (any button panel, button 1, will close all doors) and with the vent on pressurise, you will find a problem with pressurisation with the following steps.

1. Open the Sliding Hatch Door at the front of the cabin.
   - Pressure is maintained
   - The vent action will trigger if the airlock was previously unaired
2. Move into the airlock and close the Sliding Hatch Door behind you.
   - Pressure is maintained
3. Open the Sliding Door to space
   - The airlock is vented
   but
   - The main cabin, on the other side of the Sliding Hatch Door, is also vented, despite the airtight door being closed
   - This triggers a timer, switching to red lights and closing all of the doors
4. Remain in the airlock. Close the outer Sliding Door.
5. Open the inner Sliding Hatch Door. Leave it open
   - Note that the Air Vent is showing a non-pressurised cabin
6. Open and close the outer Sliding Door.
   - Note that the Air Vent is now showing green lights and the room now has pressure
7. Close the inner Sliding Hatch Door
   - Normal pressure appears to be restored

You may now repeat from step 1 until the O2 runs out.

Pressurisation problems are often difficult to repeat. If this doesn't repeat reliably for you, let me know and I shall instead upload a saved game.