These are several official design documents shared with the community. They span across over a year (1997-1998) and give an interest insight into the game.
ANNE SELECTIONS: This contain the script for the character Anne. It follows the game path and do not contain unrecorded lines (Sadly we do not have a copy of the original script).
Area Creation How-To: Guidelines and suggestion on how to create areas in the game.
Asset Creation Guidelines: Guidelines on how to create assets for Trespasser.
GUIApp Functionality Checklist: "Appears to be more sort of "how to be sure your level is working OK using GUIapp". So, it may be useful in level development, too." - machf
GUIApp Knowledge Base: Help that explains the various GUIApp functions.
Hammond Numbers (2): The first script of Hammond's voiceovers we got. Does not include unrecorded lines unlike the original one over at http://jurassictime.trescom.org/
Scene building checklist: Checklist of things to check before submitting a level.
TRIGGERS - Temp 0705: An early version of the various triggers used in the game. Earlier version than the one found in the source.
Walkthrough 8-1-97: A really early version of the type of idea the devs had for the levels. Includes ideas for the lost Plains level, as well as a completely different layout of the Town level (that was never started).