ok, So ive re-added the files back into the video tab on the left hand side via clicking "add files" and added them from my various folders, where before there was just the one gif of homer bush. I then went and saved the project as a typical Videopad file VPJ and gave it a different name. I also went and cleared the cache of 357mb of stuff. I dont know what you mean by project file AS? So far the video files are all still unchanged though despite all of that.
After hovering over some of the greyed out files on the timeline, i noticed that its only recognising them as audio files. So i selected "restore linked video files", where Videopad promptly crashed. Repeated attempts have also resulted in crashes. SO it seems that the former mp4 files are now only thinking they are audio files, although still being located on the video timeline and not the audio timeline. As in, when i select these files, it has mp4 in the names, but it says "file type: Audio". Meanwhile if i pick up one of the files from the far left tab and dump them anywhere on the timeline, it appears just fine, despite an edited version of the very same file now having these issues.
As for the narration quality, its because i sped up the speed of the audio file, and i lack the knowledge to fix the resultant echo effect from it. The video past the 3 minute ish mark has nothing on it as its not yet finished.
Additional Edit: I went to one of the greyed out videos that still has its original audio on the audio timeline. I deleted the greyed out videofile, then clicked on its original audio file below it, and selected "restore linked file", which promptly made the video reappear. Not sure if i can go ahead and do this with all of them, because doing so would probably restore them but without all of my edits, and at the same time most of them dont have any linked audio files at all so its not 100% possible. Just throwing out whatever info i can to help narrow it down for you folks in the know.