Crashing when I try to look at whole project (top level document) - any advice welcome!!

note (Oct 18): I divided the book into two smaller projects. I started with two fresh scrivener projects and copied the material into them.
One of them still is crashing when I try to look at the whole project.
Any clues as to what is wrong?

[size=85](posted earlier in tech support but perhaps more rel. here)[/size]
I have a large book project. When I try to look at the project as a whole, Scrivener crashes.
I just tried to see how large is it, and noticed that the word count for the whole project is wildly off, showing the project as a whole as much smaller than a single section - perhaps this is related?

I’m quite concerned, as the book is going to get larger. There is very little media, pictures, etc. but many subdocuments.

This is on Windows 10, a desktop with plenty of memory and disk space.
This has been happening for several weeks. I just installed 1.9.9.0 and the problem is still there.

thanks,
Judith
Screenshot 2018-10-07 10.35.30.png