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Modding tutorials - Welcome to Sim Settlements

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Content of this page is subject to changes, while I am working with the series and formatting the text.

Welcome to Sim Settlements.

This guide is a collection of posts, which includes modding basics and tutorials for popular tools.

In this post
  • 1. Activate modding
  • 2. Nexus Mods and - quick look
  • 3. File extensions and load order basics

1. Activate modding
First steps to take is to activate modding for your game. What does this mean? Game does not read third party resource file archives by default. This feature must be activated from configuration files. You will need to edit in to 2 files to make this happen.

Make sure that you have run the default launcher of the game at least once. This will generate proper configuration (INI) files for your game.

You will do these edits in your Documents > My Games Fallout 4 section. First I recommend setting File name extensions visible.
  1. Open the location folder. Click the small gray arrow next to question mark at right top corner to expand the view. (See picture)
  2. Select File name extensions active from the list. (See picture)

To: Fallout4Prefs.ini

To: Fallout4Custom.ini

If you do not have Fallout4Custom.ini file
  1. Open Notepad. This will create a new file for you.
  2. Add the content that was supposed to go in to Fallout4.Custom.ini
  3. Save the file with Save as... option. Select Save as type: All Types (*.*)
    Make sure to save the file as Fallout4.Custom.ini and not accidentally as Fallout4.Custom.ini.txt.


2. Nexus Mods and - quick look
There are two standard locations to get mods for your games.
  • Fallout 4 in Nexus Mods and Community
  • Workshop

This guide will have specific instructions for both locations. As a fast overlook, both of these sites are free and both require registration. Neither of these services spam you e-mail, like some other would.

  • You can create an account to Nexus Mods, by filling the registration form. Please read their Terms of Service. The login page might look a bit taunting at first, because Nexus lists all optional memberships first on their page. You do not need to select any of these. Proceed to create your free account from the bottom of the page. You can now download and install content from Nexus mods with your account. It is recommended that you use a mod manager like Mod Organizer 2 or Vortex. These tools are presented in further articles of this guide.
  • You can access to Workshop directly from your in-game Mods menu. You can download and install mods from this location, after filling the registration. You do not need third party mod manager to install mods from Bethesda Workshop. However, you will still need to pay attention to load order. Bethesda Workshop content only uses archived resource files (see BA2 from below) and has few other restrictions in place. Bethesda Workshop works well for Sim Settlement purposes. People looking to install more advanced mods may want to consider creating account to Nexus Mods.

3. File extensions and load order basics
Fallout 4 uses several files. This section helps you to understand what they are and what they do.

Files appearing in your load order
  • ESM: Elder Scrolls Master file. Official files and DLCs are shared with this extension. They are greater files in terms of modding, allowing mod authors to assign keywords and forms, so that they are properly used by lower tier plugins (ESP.) Sim Settlements main file is called as Sim Settlements.esm. As a rule of a thumb, ESM files always load above ESP files, though some ESP files might especially be made to appear in the middle of them.
  • ESP: Elder Scrolls Plugin file. This is the most standard file type you will see. Addons to Sim Settlements are using this file type, using Sim Settlements.esm as their master. All Sim Settlement addons should load after Sim Settlements.esm file.
  • ESL: Elder Scrolls Light Plugin file. This plugin type was added to game, when Creation Club was released. It does not interfere with standard plugin limit (256) of the game. While the file type is mostly used by Creation Club, mod authors might also use the file. ESL is fairly limited file type, so it is rarely seen in standard mods you might download.

Files in your Data folder
  • BA2: Bethesda Software Archive 2. These archive files include textures, meshes, scripts and similar resource files. They are loaded with respective plugin file, according the load order in your game.
  • Loose files (no archive). Files distributed outside of archives. These files will win conflicts against all resource files in your archives. These files do not have any respective plugin files to load them. Loose files can be both beneficial and problematic. They are beneficial, because you can usually just swap loose file textures in and out from your game, without causing problems with it. They can be problematic, if you are not certain what you have installed and something is overwriting your archived files in unwanted ways. Loose files are one big reason to use mod managers, to avoid problems with multiply files lingering around your installation folder.

See more about load order and tools to manage it from following chapter of this guide. Mod Manager specific articles will explain how to work with your load order with them.

In the series

  • Load order and resource priorities
  • Save file safety instructions (Coming soon)
  • Modding from Bethesda Workshop (Coming soon)
  • Modding from Nexus Mods (Coming soon)
  • Modding with Mod Organizer 2 (Coming soon)
  • Modding with Vortex (Coming soon)
  • Creation Club (Coming soon)
  • Advanced: Merged Patch and Bashed Patch (Coming soon)
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Load order and resource priorities

In this post:
  1. Understanding the load order
  2. Understanding resource priorities
  3. LOOT

1. Understanding the load order
Load order is the hierarchy between plugins (ESM, ESP and ESL) in your game. These plugins contain records, which are editing official master files, or reading data from them. Plugins can also edit other plugins above them, or collect information from them.

All files in the game are using Fallout4.esm as a master. They can also use other official DLC files or mod files as masters, depending on which records and resources they need. If mod uses resources from Far Harbor DLC, then it requires the respective ESM file as a master. This is true, even if mod wouldn't use records from DLC, because ESM needed to load the BA2 archive that contains required resources.

Official plugins and resources are installed in to your ...SteamApps\common\Fallout 4\Data folder. If you have all official DLCs, then list of plugins is the following:
  • Fallout 4.esm - Main game
  • DLCRobot.esm - Automatron DLC
  • DLCworkshop01.esm - Wasteland Workshop DLC
  • DLCCoast.esm - Far Harbor DLC
  • DLCworkshop02.esm - Contraptions Workshop DLC
  • DLCworkshop03.esm - Vault-Tec Workshop
  • DLCNukaWorld.esm - Nuka World DLC

Sim Settlements is designed in a way that it only requires Fallout4.esm as a master. Addons to it may require other DLCs as master. Pay attention to requirements, when downloading and installing Sim Settlement addons or other mods in to your game. If one of the installed mod is missing a master, then game will not start. It will crash directly after Bethesda logo instead.

How does the load order work?
Plugins in the load order include records. Game will load them from up to bottom. Files lower in the load order have higher priority. If there are conflicting records in your game, then last loaded records will win the conflict and take effect in your game.

We can observer this behavior by using Unofficial Fallout 4 Patch as example. Far Harbor DLC has a conflict with the main file. This is considered as an inconsistency between files, so Unofficial Fallout 4 Patch project team has moved to fix it in their mod. DLCCoast.esm changes the sound and type of Yellow Belly Syringe. These edits made chemical syringe to sound and act like a generic drink, instead of chemical syringe it was supposed to. In the picture below, Unofficial Fallout 4 Patch corrects this mistake by changing records, while having both Fallout4.esm and DLCCoast.esm included among it's masters.

Records from plugin files do not always conflict. More often they add new records and keywords in to game, instead of editing other files. Most mod files adding new keywords are EMS-files.

Setting up your load order is important matter, because wrong type of conflicts can cause instability and oddities in your game. Basic rules are easy to understand. Solving conflicts between mods otherwise requires that you pay attention to mod author notes and instructions about conflicts and solving them. Most mods can be made compatible with a proper patch.
  1. ESM files will always load at the top of your load order. Notable exception here is Unofficial Fallout 4 Patch, which is an "ESMfied" ESP file and loads right after official DLC files, despite if there are other ESM files in your game.
  2. Mods acting as masters to other mods will always need to load above their child mods. Mods acting as masters to others are not always ESM files. They can be ESP files as well.
  3. Patch type of mods will load below mods they are patching. This is important to note, because patches do not always have set masters and you might accidentally place them in to wrong position.

There is a tool called LOOT (Load Order Optimization Tool), which attempts to sort your load order automatically. We will talk about LOOT later in this post.

2. Understanding resource priorities
Resources are files that contain information outside of plugin file. These files can be scripts, meshes, textures, DLL-files or even JSON files. They are usually packed in to BA2 files. These archives are loaded with the respective plugin. If plugin is disabled, then these archives and their content are not loaded at all.

Resource priorities work like your load order does. Content in the archive gets loaded with the plugin file. If there are any conflicts between resource files, then files loaded last will take effect in your game.

Standard users do not really need to pay that much attention to resource priorities, when dealing with content packed in to BA2 files. It is important to understand how resources work and what to look, if you suddenly see wrong sort of content in your game. Because archives are loaded with plugins, then conflicts can often get solved by changing the load order.

Not all resources are packed in to archives. These are so called Loose Files. These files do not load according to load order and act as direct replacements to files they edit. Loose files will always win all conflicts against files in archives.

This can be both practical and problematic. Loose files do not have plugins, so changing them do not cause record change shock for your game. You can just swap loose file texture mods in and out, without worrying about damaging your save files. However, they also tend to cause more loading in your game than archived ones. Loose files are also harder to uninstall, unless you are using a proper mod manager that makes the process easy for you.

LOOT (The Load Order Optimization Tool) is a load order sorting tool for Fallout 3, Fallout: New Vegas, Fallout 4, Oblivion, Skyrim and Skyrim Special Edition games. It attempts to sort your load order, by using it's own file detection system and master list.

LOOT can be downloaded from here:

Using LOOT
For basic use, LOOT is a very simple tool.
  1. First use: I recommend that you initialize LOOT outside of any mod manager you might be using, after you have installed the tool or updated it in to new version. LOOT may fail to detect the game and download master files otherwise. It is also important that you have already ran the game at least one after installation, so that you have proper INI-files in your Documents > My Games > Fallout 4 folder. If you are using Mod Organizer 2, then you will have to setup LOOT as an application for it, before it detects your mods. You should still initialize LOOT once outside of MO2, after installation.
  2. Make sure that Fallout 4 is detected and set active from game selction list in LOOT.
  3. Click three horizontal lines in LOOT. This will start the plugin sorting process.
  4. Lines will turn in to tex saying APPLY, once LOOT is done. Click APPLY to finish the sorting process.

You are done. Happy modding.

Please pay attention to Safety instructions later in this series, before making load order changes or removing any mods from ongoing game!
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