I always try and do my NAP requests through the board private messaging system. That way I can check "receive read response", and know if they have read the message. If I see they have read it, but have not replied, then I am ready for war.
I also always send a follow-up message to the effect of "I assume that your silence means you are agressive towards me". That sometimes will get people off the fence, and make a reply.
I don't consider the in-game messaging for NAPs. Too hard to remember, with no way to search back 10 turns or whatever and see what was agreed to. I only use it to break NAPs
