In order to add subtitles you need to have a subtitles text file and add them that way. There is no other way to do it and even so they subtitles might not sync up to the actual words spoken on screen.
Have subtitles but you dont do it same way as use to do it with earlier versions with .srt file. Sometimes it is a different extention. Does anyone know how to do it wit the current version of this s/w?