Tweaking Tips:

• Turn the screen brightness (in the Options/video menu) all the way down. Your game will only be slightly darker, but the shadows will look way more realistic.

• If you happen to have graphical problems, such as a flashing screen, turn off the triple buffer in the extended video options menu.

Registry Hacks

You'll need to open the Registry Editor to change the following settings. To start it click on "Start", click on "Run", type "regedit" and then hit Enter.
A screen with a menu appears. Now, double click on "Hkey_Local_Machine", then on "Software", "DreamWorks Interactive" and then on "Trespasser".

• click on "Max Recommended Tex Dim" and set the existing value (80) to any value up to 100. This will double the Texture resolution.

• click on "Z Buffer Bitdepth" and set the value (10) to any value up to 24. The entire game will become more clear this way.

• click on "SwapSpaceMB" and enter any value you want. This will allow the game to create more "second" level files. But remember that the value entered is equal to your hard drive space you wanna use up. So don't set it too high, or the Computer might crash.

• click on "Gore" and enter a value between 1 and 3 , this will set the blood shown in the game.

Play Trespasser at night

Open the game first and load the night level. Afterwards load any map you want. You're gonna be able to play the map at night now. To turn of the night-mode, you'll have to restart the game.

How to teleport objects

Ever wanted to teleport and to take a certain object with you? well, if you keep the object in your hand while teleporting, it is gonna get teleported with you.

Committing suicide

Anne is unfortunately able to commit suicide. To do so simply press a gun (which you should be holding in your hand for this) against a wall. If you get (un-)lucky , you might kill yourself.

Shock absorber

Any Object in the game can function as shock absorber. So if you happen to fall down a cliff, try to land on  a Dinosaur/box/tree or whatever. Though you still get hurt, you might actually keep on living.

Super-Anne

Anne can sometimes fit through small inches of space (eg.: gates, doors etc). Try to press her as hard against the inches and she might fit through. If it doesn't work that way, throw away all the stuff you're carrying and try again. Many times it actually works.

In-game tips & tricks:

Fooling the T-Rex & Albertosaurus

Often you can simply run around him in circles, since it takes him a long time to turn around. Play tag with him for a little while. That is an easy and good way to escape. Try to run around many objects (such as boxes). The T-Rex will often try to get over them, slip and fall. But remember: Standing still doesn't work in the game (though it does in the movie). The T-Rex will still try to get you. 

Fooling the raptors

Try to sidestep when the raptor attacks, many times the raptor won't follow right-away. Also run through many trees if you can, many times the raptor will have to run around them  and not actually through a close treeline. Another way would be to enter buildings. These areas are forbidden for raptors and they won't try to follow. At later levels you can also try to make raptors fall down the mountains and die. simply sidestep, when they attack and they will run into their own death most of the times.

How to get to the basement

Try using the teleport cheat: First press Ctrl + F11 and then type: "tele 0,0,2" should work most of the times. You should save before doing this though, since once in a while you might get killed by raptors waiting there for you.