Okay, here's what you do.
[list type=decimal]
[*]Open a window (Windows Explorer) and go to where you have
Shogun_-_Sengoku_Jidai.rar and
Shogun_-_Sengoku_Jidai_patch_1.rar.
[*]Open another window, without closing the first one, and go to
C:\Program Files (x86)\Steam\steamapps\common\mountblade warband\Modules.
[*]Now go back to the first window. Drag
Shogun_-_Sengoku_Jidai.rar,
with the right mouse button, down to the task pane (folder names at the bottom of the screen) and move the mouse over the Warband Modules folder. Don't let go of that mouse button just yet. When the Modules window opens up, continue to drag the .rar archive
up until it's where files are shown (or would be if you don't have any other mods installed). Release the right mouse button now in a suitable spot, but make sure you don't release it directly on top of any other mod folders already there.
[*]A little menu should pop up. Click
Extract Here. Wait until your computer is done extracting the files to the intended location.
[*]When it's done, go into the
C:\Program Files (x86)\Steam\steamapps\common\mountblade warband\Modules\Shogun - Sengoku Jidai folder you just created.
[*]Without closing the currently opened window, open your other window where you have
Shogun_-_Sengoku_Jidai_patch_1.rar (or find it if it wasn't in the same place as the other archive).
[*]Do that same drag and drop
with the right mouse button, except this time you're dragging the archive to the recently opened
Modules\Shogun - Sengoku Jidai folder. Again, make sure you don't drop the archive directly on top of another folder when you extract it, as you don't want to extract the files into one of the folders in that window.
[*]This time, it should prompt you that files and folders already exist with the same names. Go ahead and choose to
merge or replace what is already there.
[*]After your computer is done extracting the patch files, you should now have the mod and its patch correctly installed (I'd hope). Now open
C:\Program Files (x86)\Steam\steamapps\common\mountblade warband\Modules\Shogun - Sengoku Jidai\WSE Files.
[*]Select all 8 files, right click one of them, and choose
Copy. Don't worry, you don't need to hold down the mouse this time. Just make sure you have all of the files selected at the same time when you chose to copy them.
[*]Go up a few folders to
C:\Program Files (x86)\Steam\steamapps\common\mountblade warband. Right click anywhere in this folder (except on another file or folder) and choose to
Paste.
[*]You should now have all of the WSE files in the main Warband directory. To play Shogun, you're going to need to run
WSELoader.exe from where you just pasted it (NOT from where you copied it from) instead of the normal M&B Warband launcher. I recommend creating a shortcut, either on your desktop or on Steam itself. If you need info on how to do that, or any other WSE installation info,
take a look in here.
[/list]
I hope this is the solution you were looking for. Let us know if it doesn't work out for some reason or you have any questions.