Not much of a tutorial as its really simple and very easy to work out on your own anyway.

To get a video to play while loading your singleplayer map or nazi zombie map, do the following.

Download a program called RAD Video Tools.

The download can be found on their main page Here

This nifty little program will convert your video files (avi/wav/mov/qt and many others) into the BIK format which the game reads.

After downloading and installing, simply open the program, find the video file you wish to convert and click "Bink it!".

After this you get a whole host of audio and video compression options which you can play around with (I didn't touch anything) and click "bink".

Once it has converted (this may take a long time depending on how big your video file is so make sure everything else is closed and go watch tv) find the file (should be saved to your desktop or where the original video was.

You will want to place the .bik video you just made into the dir:

*:activisionWorld at Warmainvideo

Rename the video to:

yourmapname_load.bik

(for zombies:)

nazi_zombie_yourmapname_load.bik

(the "_load" is very important!)

Now load your level as normal and watch your intro.

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I've never done this before so I just spent the last hour making a video and figuring out, if anyone has suggestions or just enhancements that could be made to this please post them so I can edit them in and apply credit where it's due.

As a note I simply recorded about 30 seconds of my desktop and me moving a window around on it with "cam studio". It took about 6 minutes to compress the avi to bik but the quality was excellent (on widescreen).

Also it would be good to find a simple way to package these bik files with usermaps.

(my bik was 2,000kb, while the stock ones are at 50,000 or more so there's room for some quite long videos here)