Matt,
I just finished my crib for my son who is 7 weeks away. I went with 2" spacing on the railing except on the two end spaces, where i went 2-3/8", but i only did that because it helped the other rails equal out to 2".
I used alder because we were staining really dark, a deep chocolate brown and I personally am not good at staining maple.
as far as hardware, i would look into a company called "products america", they have the hardware kit for the wood magazine crib that was in the sept or nov issue and they were running a special on it. they have a website. I think with the wood magazine as a guide it would be a fairly straight forward project. unfortunately the crib I built was based on a picture so I couldn't follow the mag article.
how do you plan on doing the construction of the rails? i believe i remember you saying you own a mortiser so i am assuming you will be taking that route. the mag offers a different approach for someone without a motiser or mortising abilitites.
good luck with the build, i am sure you will enjoy it. keep us updated.
chris