There is no way to insert a multimedia file into Word document directly. With the “Media Files” add-in, now you can do this by insert a special hyperlink to the Word document and then the add-in will embed the media file into the created web help.
This add-in supports various types of multimedia files, such as Flash (.swf files), Windows Media Video (.wmv, .mpg, .mpeg etc.), Windows Media Audio (.mp3, .wav, .wma, .midi, etc.). And the add-in can be extended to support other multimedia files.
[Example]
The above flash file is inserted by insert this media link:
macrobject:media::.\InsertFlash.swf,width=300,height=60