Another watertight door for my Nautilus model. Contains both open and closed version, as well as a simple shape that you can use to cut holes for the frame. The dimensions of the door frame are 80 x 180 cm, and it's 22 cm thick, to fit inside a 20 cm thick wall (but this can be adjusted by pushing the side with the bolt heads inwards or outwards). I imagine it fits best if placed 10 cm above floor level. Note that there is a simple mechanism for holding the door in place when open, to avoid crushed fingers. This should be attached to a wall (in my case this wall is just 5 cm from the edge of the doorway, allowing an opening of just 85 degrees, but you can easily adjust this according to your needs).
Feel free to improve on it in any way you can.