Hi there, i found something really interesting for making good introductions, and i was so happy that i wanted to share that. ^^
!!!TUTORIAL FOR WINDOWS!!!
Roq file for zeq2 intro:
1. Download ffmpeg here: Ffmpeg.org
SEARCH FOR YOUR OS AND OS VERSION (XP, 7, 8, x86, x64).
2. Extract the folder where you want to work.
3. Having a video in avi and high quality is recommended.
4. Put the video in the folder that contains an executable named ffmpeg (it avoid putting the entire path in the command prompt)
5. Go in command prompt and type: cd
6. Then type: ffmpeg -i .avi -ab 256k(bit rate, keep this) -ar 22050(further sound frequency of the video) -r 30(further frequency of frames per second in the video) -s 256x256(further heigh/width of the video, you can try 512 or higher but the further file will have heavy frame that will not be read by quake3 engine) .roq
Exemple:
cd C:\Users\Wh1t34Gl3\Desktop\FFMPEG\Bin
ffmpeg -i a.avi -ab 256k -ar 22050 -r 30 -s 512x512 a.roq
I had a video of 1:33 and 15mb
The roq file is 30mb now, and took me 5 min to convert.
If you want quality, try to put 512x512, not more or the game won't be able to read heavy frames and will crash and not over the initial resolution of your video (if it already has a tiny resolution, or it'll be ugly xd). (the program will say in red when some frames are too much for q3, so lower the resolution and restart the convertion)
Don't forget that the resolution must be a power of 2 (square, exemple, 512x512, and not 640x480)
Hope that helped for those who want to convert files to put them as an intro in zeq2. 
IMPORTANT:
I advice you to make a batch file to avoid typing commands everytime if you fail or you want to convert few videos..
1. Do: Win + R (exec)
2. Type notepad then press enter
3. Write your commands.
"cd
ffmpeg -i .avi -ab 256k -ar 22050 -r 30 -s 256x256 .roq"
Don't forget to go to the line after the command "cd".
4. Ctrl + S
5. Name it as you want but don't forget to change the ".txt" into ".bat"
6. Run it and it'll do everything for ya. (you can change rewrite it by doing right click --> modify)
Make some nice intros 
J'adore =)
Anonymous666