Things to note:

1. When installing mods it is first important to know that you don't want to install them into the game's directory itself as the game will likely not be able to read the mods.

Instead you should install the mods into the save directly for your user account. It should look like this, minus the "Mods" folder at this time:


It is of note that the appdata folder itself is considered a hidden folder and thus you may need to turn on the option to show hidden folders and files in order to see it.

2. Once you find the correct directory create a folder titled "Mods" within it and within the Mods folder create new folders for the mods you wish to install.

3. When installing the mods install them directly into the new mods folders you created for them, DO NOT Install them into the "Mods" folder itself as then you'll need to manually move all of the files and folders into the correct mod folder.

4. It is recommended that if you wish to install both Unification and Ultimate Apocalypse that you should install Unification first to test and see if the game detects it as Ultimate Apocalypse requires a few additional mods.

5. For Ultimate Apocalypse install the Tyranid Mod, Objective Points Mod, and FreeUI Mod. Make sure to install all of these directly into the Ultimate Apocalypse folder. It should look like this: