There are two distinct methods for the generation of object LOD data (DistantLOD folder): using the Construction Set or using TES4LODgen (now a part of TES4Edit). These methods are radically different in their selection of objects to include in the distant view data:

• The Construction Set includes all objects that have the VWD flag set ("Visible When Distant" check box checked), regardless of whether or not these objects have special _far meshes for distant view. If no _far mesh is found when the game is loaded, then the object is not shown. But as soon as you install the _far meshes, it magically appears.
• TES4LODgen completely ignores VWD flags and instead includes absolutey all objects where _far meshes are available. This usually results in many more objects included in the LOD compared to the CS output. You have to be careful which _far meshes you install, or your game will be overloaded with LOD for every imaginable tiny rock.
  

Vanilla LOD that comes with Oblivion, was generated with the Construction Set. However, the original game does not have the VWD flags set on the exteriors of forts or Ayleid ruins. This mod sets these flags on all vanilla forts and Ayleid ruins so that they could be included in LOD generation using the Construction Set.

If you wish to use the CS to generate distant LOD and you have other mods that add forts or Ayleid ruins, you can use these TES4Edit scripts to update your other mods: Vanila LOD help scripts. See in particular a new version of the script posted in the comments - this replaces the two scripts from the Files section of the mod.

To get the best results, please also use optimised _far meshes such as J3 Atlassed VWD 2 meshes.

The method for distant object LOD with the CS is then as follows:

• Download the ESP from this mod and add it to your load order. Put it quite high up.
• Make a backup of all your ESPs as some will be modified.
• Move or rename your Data\DistantLOD folder. There should be no such folder in your Data directory.
• Start TES4Edit and load your entire load order into it (or at least everything that modifies the Tamriel worldspace).
• For each mod that adds or modifies forts or Ayleid ruins, click it, go to Worldspaces, right-click Tamriel, select Apply Script from the menu, then select your new script that sets VWD flags and let it run.
• When all mods that need updating are updated, exit TES4Edit and save all your changes.
• Start the Construction Set. I use the CSE, but also the original should work.
• Load all the mods that modify the Tamriel worldspace (the same ones that you had loaded in TES4Edit). Do not set an active file.
• From the menu select World -> World Testing -> Update distant LOD data. Then from the dialog box select Tamriel and click Export This Worldspace. This will take a long time, this is normal - it's a big worldspace. This will create Data\DistantLOD folder and fill it with files.
• Done! Exit the CS.
• If you had distant object LOD of worldspaces other than Tamriel in your original DistantLOD folder, you can either generate new LOD for them using the above method, or simply copy over the old files. These will be all the files that begin with anything other than "Tamriel".
  
  

I used this method to generate distant object LOD for the entire TWMP Tamriel, including all available provinces. I can now once again play the game without crashes.

Note that distant object LOD (DistantLOD folder) is only for objects such as buildings, rocks, trees, etc. It does not include distant view data for land. Land distant view data is generated through an entirely different process and in no way conflicts with object LOD data.



Advanced usage

For those of brave heart and in particularly those who know what they are doing, I have uploaded an xEdit script that deletes all references that don't have the VWD flag set. The intention of this is to emulate the CS method of object LOD generation using TES4Edit. This is needed for large worldspaces such as Tamriel with more provinces than just Cyrodiil.

The intention of this script is this: load your mods into TES4Edit, select all of them (or only those that you want stripped), run the script to delete all references that don't have the VWD flag set, then run "Generate LOD" from within TES4Edit. Quit and DO NOT SAVE your mods! Because of course now they are completely ruined. (If you did save them, there should be backup, assuming you didn't turn off that useful feature.)

Note that if you are loading all available provinces of Tamriel and then some, the standard 32-bit version of TES4Edit will run out of memory. Run the 64-bit version instead - it is a little slower but can use more than 2GB of RAM. If your PC has less than 4GB of RAM, don't even start.

If you find yourself using this script often with some mods, you can create a delta patch to load specifically for object LOD generation with those mods to save you some time.

This script is DANGEROUS and I won't be responsible if you botch up your mods!