Presenter 360 wants to upgrade Presenter 13 file... can't find the .quiz files and then freezes when I try to remove them

So many of my 100 or so presenter files come up with this error:  I open the file in Studio 360, it says that I have to upgrade, so I do, then it can't find the .quiz files (that's because they were moved nearly two years ago... I know this), so then I just say "okay, don't bother, just remove them... then I wait for a long time and it never finishes "removing" the .quiz files and I have to crash the application to get my program back.

Then start over again.

Studio 360 seems incapable of removing those files.  What do I do?

And before you tell me to "rebuild it"... this is what I have to do every time, it's  painstaking process that takes hours because when I try and create a new presentation and "import" the old slides as your support team instructs, I lose all the audio and all the video and have to plug everything back in slide by slide there are about 140 slides and it takes 5 to 10 minutes each while I root around and try and find the correct audio or video slide... even if I got it done in 90 seconds time 140 slides it's still three and a half hours.

And if you say "well at least you can export the audio and re-import it" that doesn't work either because I can't get the presenter file open long enough to export the audio in the first place.

It seems (just a guess here) that the problem has something to do with the following:

(1) The pptx file was created 2 years ago in Presenter 13
(2) I have since some up with a better storage plan and moved those files somewhere else, where all my new programs use them efficiently.
(3) When I open up the 2 year old Presenter 13 file that still thinks the .quiz files or elsewhere, Studio 360 has some issue with that and will not allow me to delete the pointers and just freezes as in the image shown below.  Jim