Following your suggestions...
I renamed the version name to "1.1".
Apparently, I DID forget to sign the file. I see a KEYSTORE file in the folder from my first (successfully) published app but do not know how it was created.
I copied that file to my present app folder (renaming it accordingly) to use as this present app's KEYSTORE file. Now, trying again to publish the app, the .apk file upload attempt produces the same error message as before: "Market requires a Version Name".
Any further suggestions will be greatly appreciated. At the present time, I am unable to publish anything to market.