Things that you'll need in order to complete this task:
WOW FOLDER- Regular world of warcraft folder, 3.3.5a.
BLP Converter- http://www.wowinterface.com/download...Converter.html
MPQ editor- http://www.softpedia.com/get/Program...Q-Editor.shtml
Photoshop, or an image editor- Up to you what you use, but i prefer photoshop.
Basic knowledge of using an MPQ editor.
Download the files above and open up MPQ editor, navigate through your WOW FOLDER (Wow>Data>EnUS) and find your LOCALE-US MPQ and open it up it will look like this: http://prntscr.com/42tk9x
Open the interface folder and find GLUES open that, now find LoadingScreens and open that. You should be here now: http://prntscr.com/42tkw8
Okay now let's extract the LOADSCREENEASTERNKINGDOM.blp and put that in a new folder (The folder will look like > http://prntscr.com/42tl9g )
Now open your blp converter folder and click and drag the LOADSCREENEASTERNKINGDOM.blp onto the BLP converter and you'll now have this: http://prntscr.com/42tmcq
Open the PNG file with your image editor and now you'll have your world of warcraft default image: http://prntscr.com/42tmw5
Go and find or create your own >>>>>1024x1024<<<<< image. I'll use a worgen image, now when you're saving your file make sure you save it as: http://prntscr.com/42tnhz
Now that you've saved your image delete your old BLP FILE:http://prntscr.com/42tnwd and now click and drag your PNG file onto the BLP converter.
You're almost done now, create or edit a new or an existing custom MPQ patch and create a new folder inside the patch (Interface>GLUES>LoadingScreens) and add your NEW BLP file: http://prntscr.com/42tox6
Now put your patch into your WOW FOLDER>data DELETE CACHE aswell. Log in, go to a EASTERNKINGDOM zone and enjoy your new loading screen!!!! >>http://prntscr.com/42tq70
You can do this for any other loading screen as well!
If you have any questions or comments please leave them in the section below!