btw on a side note. I think that when you put the movie files into the content folder, the editor should automatically use a relative path. This is atm not the case, at least wasnt for me. I imported the movies from content/movies but the path in the source file asset was absolute, thus packaging worked and the movie got packaged but when moving the package to another PC, the video loading fails.
Also there was this wierd thing that after me chaning 1 of 4 source files to a relative path with “./Movies/file.avi” for eaxmple, the other 3 source assets adjusted their path to relative. That was really weird… dont know if you can reproduce this as well but maybe check once or twice for yourself 
maybe you have that happen to you as well