I couldn't get a firm pattern on the access violations, so I just did a clean install.
I ordinarily don't install any betas on top of a beta, but I couldn't definitely remember uninstalling the previous one (which was the first version of CHS I ever used), so I'm assuming I didn't.
So far, all seems well with the clean install, but the situation begs a new question. Which files actually contain my saved clips, and are those files likely to be safe to move between beta installations?
Thanks, both of you, for your help,