Hi there! ok first off you should try the way Virgil directed you to,
by -Extracting- the files from the .rar file using the
WinRAR program, Link to Official site:
WinRAR download and support: Start
(the free download will do what you need, you don't have to buy it)
Then adding the game to uMod and activating the "use global hook" (these steps were covered on the first page of the thread so I won't re-post the images showing how).
Finally
AFTER starting the game you need to go to uMod, drag the files you Extracted (they should end in .dds) onto the open white part of uMod, and - right click > update (reload) - then go back to your game, if you did all these steps correctly, and don't see the outfit changed...
leave uMod up and simply restart the game, check it again to be sure it did update.
Then try my method of taking all those .dds files and putting them into a .zip (highlight them all, right click > send to > Zipped folder) you can name the new .zip whatever you like, and then run the game, go to uMod, right click on the white area your "single textures" is in, choose "add texture/package" and select the .zip, you should get a couple of pop ups, then just - right click > update - and go back to your game, still not working?..
again leave uMod up and restart the game.
Let me know if that helps! (or even if it doesn't!)