More than one graphic in the saved document has an ID=0

Good morning all,
A strange “problem while loading” error appeared when I opened a document this morning. When I saved and closed the document last night all was well. When I opened, I got this message, and a large majority of my path lines drawn had reattached themselves to a new point central to the main drawing. Here is a screen shot of the message:

I saw that someone had posted about this but the resolution wasn’t clear. I was curious if anyone could note why this happens. Am I creating my Stencils wrong? If we all know the root cause, then I can avoid making this mistake in the future.

Thanks again everyone for the input and help. I very much appreciate it. Have a great weekend all.