PLEASE NOTE THAT NOT ALL AVIS MAY WORK...
Download your specific AVI file.
I use DvdVideoSoft for ripping various stuff (mp3, wav, AVI) from YT.
You'll only need YT Download and YT to mp3, but you may find other stuff useful...
How to use it:
Just DL those two. Then do whatever is necessary...
Just copy the desired YT URL.
Click on YT Download and YT to mp3 (because you need the exact sound that goes with the video. ;D )
While on either of those two boxes:
The copied URL should automatically be there. If not, click "paste".
Assign your output folder...
In Youtube Download, choose any AVI file type. They're just the same.
In YT to mp3, choose WAV. When you open an AVI in MMD, there is no sound; so you'll need the exact sound from the same video...
Click Download and a window should appear.
It won't take too long to DL it, so do what you want...
If those avis don't work. then convert the avi to another format. I know Microsoft Video 1 works and is very simple. For converting videos, I use Prism Video Converter. It's not free.
It's not hard to use. Just click "Add File(s)" or whatever that thing with the + sign says. then open the desired video(s). Look down.
See that drop-down box? The first one. "Output Folder" : Where you want your video to be placed. "Output file" : Duh. In our case, we choose "avi".
Beside the Output File box is the Encoder Options. Click it. Then It'll bring up a box where you choose what compressor to use. Again, I use Microsoft Video 1, but others work well too.
All done? CONVERT.
Open MMD, of course!
background(B) > load background AVI file(L)
Load your specific AVI file. If it has any gibberish/Japanese letters, rename it/delete the gibberish/Japanese letters.
When it loads successfully, (It may take a while depending on the number of frames.)
Load the specific WAV file. (I bet you know how to do that btw)
Now look for the ending frame. How? I'll help you.
1 minute = 1800 frames
DO THE MATH.
input the start frame (wherever you want to start) and end frames in the play box (i lol'd)
If you want to do something like what I did in here...
After you've loaded the video/wav, open a screen or stage with a screen. I used the screen that came with Anomaro's PMD stages.
background(B) > ON.mode03(B) Tadah.
Oh dear... the video is still playing on the BG. What do I do?
background(B) > uncheck show background AVI file(A)
Then the video will only play on screen/stage.
If you have any more questions, just post them below. I'll try my best to help.