Multiplexing Audio and Video
Lauch bbMPEG and press the "Start Encoding" button on the lower left corner. Then press the "Settings" button to get the screen shown below. If you use Windows XP, you have to press the Load button on the upper left of the main screen and press cancel to close the window. You have to do this to preven bbMPEG from crashing when you load you audio and video files.
Open VS is where you load you video file. Open AS 1 is where you load your audio file.
Next go to the "Program Stream Settings" tab.
Select SVCD as the stream type and select the type of pulldown you did when you encoded the video.
The press OK to close this window and press "Start" to begin multiplexing. After its done, you should have a muxed mpg file that can be burned using Nero or any other burning software that will burn SVCD's