I've never had a problem getting seats pre-assigned on MH using NW award tickets. Just make sure you call MH direct, as previous posters have mentioned.

The 30K intra Asia business class award is one of the few remaining amazing FF deals out there. Yeah, it would be great to get the new seats, but you can hardly complain if you get the old seats as MH is really a quality airline to fly. The lounge is KUL is great too, make sure you make a visit.

Kezza