The most recent crash occurred when I deleted several short paragraphs, no more than a few sentences, in the middle of the document and then inserted this as a placeholder/reminder:

[Application]

As soon as I hit the closing bracket an error message popped up:

When I hit the Reload button, the document was truncated at the end of page 4. Fortunately, I was able to revert back to an earlier version.

Prior to this event I had another "crash" with this same document. I had highlighted a paragraph and hit the DELETE key. The same scenario happened. I was asked to Reload the document and when I did, it was truncated at the end of page 4.

Any idea what might be going on?