Sorry... double-posting, but there was no 'edit' option. Just wanted to say thanks
to all for the great help, I got the issue resolved. Completely removed the device from the PC and then rebooted. The computer seemed unable to see it after that because it was not there under Unknown Devices, but a 'Show Hidden Devices' revealed it under some weird category. Not sure why, but in any case, an update to the drivers allowed me to install the Realtek software. Everything runs great now.