Old version of MM creates “locked” movie and new version freezes when adding video with sound

I've created a movie (pictures, video and music) using movie maker version 6.1 on windows 7 (which also has installed MM vers 16.4).   The 6.1 version has a lock symbol on it in my video  folder and won't play after recording on a cd.  Assume the lock is somehow affecting the recording so it can't be played on the dvd player (though will play on my computer).  Tried duplicating the movie using vers 16.4 and every time I add a video it shows loading audio data and freezes.  Very frustrating.  Have tried the several suggestions about checking codecs and windows essentials but there  seem to be no problems.  Appreciate any help possible.  Many thanks.