Got it working after 2 hair pulling hours! I'm fairly certain this was a user error. Anyhow, don't make the same mistake I made (I am not referring to the mistake of upgrading to Windows 8, although, by itself, upgrading to Windows 8 certainly is a huge mistake). The mistake I made was leaving the Toneport UX2 plugged in during the entire Windows 8 upgrade. Perhaps I was just trying to see if Windows 8 and Line6 drivers would play nice and be smart. Ha! Of course not! What really fooled me is that for the very first half hour or so the Toneport worked. It was around 30 minutes later something got weird. Finally I tried the other three USB ports on my laptop. They all worked. Stumped I plugged the Toneport back into the USB port that was having a problem. No luck--that one USB port still failed. I began searching Google for things like "re-install USB port", and finally ran into a thread that had the proper advice (below).

First of all, listen to the Line 6 installer in the first place and you should not have this problem. Leave the Toneport unplugged during driver installation. If something weird happens during this phase your registry will be corrupted with bad USB mojo.

If you ran into my problem (one out of four USB ports failing under Windows 8), just go to the device manager, uninstall all of the USB devices (I did not use safe mode to do this though that is what was recommended), and re-boot the PC. The USB hubs and other USB crap re-install automatically upon re-boot. Finally, I ran the Toneport driver installation again and this time it worked on the port that was acting funny. Seems like the removing of the USB deivces from the device manager cleaned up the bad USB "mojo" within my registry. Almost started with regedit but thankfully found the proper advice first. Good luck!