Please correct me if I'm wrong, but I don't think the following has been done:

One way ticket (BKK-SFO), select Business Class & Mileage Upgrade from Full Fares. If search by price, only flights with availability come up. If search by schedule, all sorts of combinations/possibilities come up, but clicking on anything that doesn't come up in search by price leads you back to the original search screen with the msg: "We're sorry, there was a problem processing this search request."

Not quite a web bug, but thought I'd mention it, when I repeatedly called the phone reservation desk, the agents were not able to see the same availability that I could. In this case, they did not see upgrade availability on a BKK-NRT-SEA-SFO routing, whereas nwa.com did, and happily sold me the ticket.