I've been looking for the past few days at the BA site trying to book using Avios for WAS/BWI/IAD-LHR or LAX-NRT. No dice.

I've been using the Qantas site to try to find availability. It has its quirks (like you can't push the back button), but it is functional. I suppose it also helps that I'm trying to find flights on OneWorld partners (well not for WAS-LHR).

I hope they fix it soon.