Hi ralphps2000,
This is one of those moments when the way you're doing something is the right way and PD is less "pro" and doesn't provide you with an adequate solution.... perhaps. The subtitles can not be locked as can other tracks.

Please try the following workaround.
1. Place a long video/image in track one, sufficient to cover the whole length of your audio and subtitles.
2. Uncheck the Enable/Disable display for the video (and audio if there is any with the video)
3. Place your video and images for your project in the below/higher numbered tracks.
4. Editing the video files using the "Split" option and the keyboard controls of "," and "." for single and multiple frame movement.

I think this workaround should work. Please let me know if it doesn't.

The correct editing method (which you want to do) for having audio in a video is to insert the audio in first and then match up the video.

Dafydd
PLUS
Just to add: In Preferences > editing > Check, Link all tracks when inserting/removing content in timeline

Hi Dafydd,

Your solution works perfectly! Thanks so much! It does protect the subtitles. The program may not be perfect, but for the money it is a very powerful and creative tool that can produce professonal results. Again, thanks. I didn't have to redo my project!