Update:
I unloaded migrations libraries 11, 12 and 13 just as a check and still have a clean library report,(no "missing objects").
Also took a look at AMT's hot linked files association and that's good.
The "missing" libr. objects did not cause problems, just wanted to chase it down while I was cleaning up some other missing parts I had made.
Thanks again everyone for the help, especially on a holiday!