Play a mpg movie before the mission starts . The Render id no is the number of a mgg files in your 'Driver' CdRom under the FmvData Folder.
Sample_number is the index of a sample to play after the render has finished but while it is still onscreen. A -1 value signals that no sample should be played.
Most renders will require this as -1, so you may leave out this parameter and it will default to -1.