I have a similar situation. I am in the middle of an itinerary AMS-SEA-AMS in economy class, Gold and Silver members with Air France/KLM Flying Blue. We are flying on a KLM flights operared by NWA, although with the merger and the increasingly unintelligable baggage rules, it it always confusing whose rules we are following.

On the outbound portion, we were both, as elite members, to check-in two bags free of charge as expected. No problems.

But it now seems NWA/Delta will only allow us to check-in 1 bag free of charge, despite having bought KLM tickets. I sent an e-mail to NWA and received a response that was basically a copy and paste of the baggage rules.

Can anyboyd help? Would it be better to post in the Delta forum?