Turning Dresser Cabinet into Humidor

I have this antique dresser in my room, and the top cabinet half is not being used currently. I would like to turn the top half of it into a humidor to store my Cigars but had some questions.

#1 - The doors are not 100% air tight, but are pretty close. This would be a good thing correct? to allow slight air flow and what not? or do I want it 100% air tight?

#2 - Would I need to line the insides of the cabinet section with anything?

#3 - Would having humidity inside warp the dresser significantly?

#4 - What would be a good humidification device to put inside of it?

Thanks for any help or suggestions!