Good demo. Really liked it. Been waiting for a game like this since seeing the movie as a kid 20+ years ago.
Here's some things i feel would make it even better:
Hide in the bathroom and if he's chasing you when you go in there it gets destroyed and you get eaten off the toilet like in the movie.
Use flares that the T-rex will react to and follow if thrown.
T-rex reacts to the flashlight (currently it does nothing apart from making things easier to see).
T-rex able to turn the cars over and crush them like in the movie and you have to crawl out. You could make it randomized, sometimes he turns the car over, other times he just breaks through the roof and eats you like in the current version.
T-rex stops and sniffs you if he bumps into you when he's walking around, even when he doesn't know you're there apart from by physical touch.
Be able to go inside both of the tour cars and find and use the night vision goggles in Lex & Tim's car.
This next suggestion might be quite a lot of work but maybe add the other human characters in the cars with some basic AI that you could order to follow you to safety down the road.
Get rid of the trees blocking the road and make it so you "escape" and beat the demo if you make it a certain distance down the road without being spotted.
Puddles on the ground.
Make the rain drops on the car windows actually run down and not just stuck in one spot.
Controller support for people who find playing with a mouse & keyboard too hard.
Thank you for your work so far.