chronic beachballing syndrome

I can open Scrivener fine, just that that when I save work, I encounter problems. it beachballs and I have no way out except to Force Quit.

example: I tested it out just now. I took a snapshot, which worked, and then I tried clicking on the list of snapshots. Scrivener started beachballing until I forced it to quit.

similar to what I had happen earlier with another document:

I thought it might have to do with the numbers of Snapshots. ordinarily I take a lot of them. but I tried deleting some of the earlier ones and I still had problems. length of the document: about 65,000 words, not counting notes, no illustrations. had a video file but I deleted that, to, again, save memory.

Instead of snapshots, you could make backups of the project.
Each may include a date/time stamp as a distinction.
novel-draft 2013-04-13
novel-draft 2013-04-14
novel-draft 2013-04-14 23.10.aip
And you may backup to your local drive, Dropbox, Box, or iCloud folder.
That would reduce your project size and free up memory.
You might also run Onyx to clean up system files
And use Activity Monitor to see if you need more memory.