It turned out to be user error. I inadvertently opened the DBL version rather than the current version. I guess that I wasn't expecting to see the published version available as a resource, and the version I wanted was off the bottom of the visible area. When I scroll to that, it opens fine, and I can see all my data.
Checking that the files were there and correct was a clue. Checking various settings I saw that I was on a setting of restricted Internet, but changing that didn't seem to make any change. I'm on a reasonably fast connection, so that wasn't an issue. I did notice that the Mercurial config was empty, and adding the path didn't seem to change much.