If you have the No One Lives Forever GOTY edition, you will find the file NOLFTools001.exe included in your installation. All you have to do is to extract and install it. For older versions of the game this file will need to be downloaded from one of the various sites that still have it available.
This is a self extracting zip file that contains a SETUP.EXE that will unpack to C:\NOLFTools\. Install the tools to your game, by running the Setup.exe in the new folder.
You may have to run this setup as Administrator in order for them to work, especially the extract game process
1. Install tools and extract the game
First off, run setup and let it install Dedit, Modeledit and the various other tools. If you follow the default installation locations, you will then find these programs in a newly created Tools folder inide the main Nolf folder. I will skip this step as it is a pure install.
The setup should also ask you if you want to extract the game resources, then it will run the process you see below.
(If this doesn't happen, try to run unrez.bat as Administrator)
The end result would be a new folder called NOLF Which is located inside the Main Nolf folder.
This is the whole game, except source code, extracted.
2. Setup Dedit
Go to your Tools folder and find Dedit.exe, set administrator properties to it and start it.
In most cases unless you plan on creating a entirely new game, you never select New Project from the file menu. Go to File -> Open Project and browse the newly created NOLF folder for NOLF.DEP.
You have now opened the Game project and we can go to File -> New World, which will be the actual thing you will be editing when building a new level or multiplayer map.
There are however a couple of things you should configure before going crazy in here.
You will have to set a few paths and arguments to make sure resources are found, processing is correct and that you can run the level from dedit.
I have my game installed on G:\NOLF\, so any references I do should be modified to fit the installation path you chose.
Then hit ok.Executable: G:\NOLF\lithtech.exe
Working directory: G:\NOLF\
Program arguments: -rez nolf +runworld %WorldName%
This will tell the engine to load the Extracted NOLF folder and your level
(if you want to load optional rezfiles such as widescreen patches, modernizer when test playing, they can be added in Program arguments, but this is not required for the game to run.
Example: -rez nolf -rez custom/modernizer.rez +runworld %WorldName%)
3. The Level Processor
Click World -> Process
The Checkboxes should be set to preferance, this is mine however.
While building I keep Fast Approximation checked, but this should be unchecked on the final process before releasing the map.
The project directory is where NOLF.DEP is in all cases.Project Directory: G:\NOLF\NOLF
Extra Parameters: -nosnapnocsg
The extra -nosnapnocsg is optional. It all depends on your building methods. You can leave it empty if you plan to build without NoSnap.
You should now be all set to edit