Nothing fancy at MCO or ORD. The US essentially does not have departure customs inspection — with the exception of one remarkable case in 2007 where a woman booked a one way trip ORD-PEK and was subjected to a "random" post-security check of her bags where government agents found thousands of electronic documents which, they somehow determined at the time, were stolen trade secrets from Motorola that were being smuggled to China (http://www.law360.com/articles/28485...-china-witness , http://articles.chicagotribune.com/2...-trade-secrets ).

But with that rare exception this never, never, actually happens. You'll be asked to show your passport at check in at MCO and possibly at the gate at ORD, but there is no formal customs or immigration process for exiting the US.

Your 2hr15min layover in NRT should be enough time to transit through the international-to-international transit area. This is clearly signed. There will be another security screening but your passport won't be stamped (you won't enter or exit Japan). Be sure you have your onward boarding pass NRT-TPE available — best to get that at check in if possible.