Use the keyboard arrow keys, to go inside of the ship (using the ramp)…
Yes I did it! But then what? How to get rid of that Klingon and open the door that's behind him, and then make a tour of the ship's insides? The doors aren't responsive to any usual keyboard key combinations...
Yet if you jump high enough then you partially fall through the ceiling and can catch a glimpse of the upper floor with the control room full of various stuff to explore...
This demo was designed for Oculus Rift virtuality goggles. If you look straight down, you can see two black circles under yourself. Those are your "virtual hands" as seen from their ends and usable when running Oculus VR. At certain falling light inclination angles, you can even see their shadows on the floor...
Probably you need those hands to operate objects in the scene. Without them, you can only navigate and jump, shoot ping-pong balls with LMB clicks, and toggle a flashlight with RMB clicks.
If I could complete the tour successfully, probably I wouldn't be thinking of hacking the model...