I really recommend keeping electronics in your checked luggage. DON'T carry it on. There are quite a few articles about how to travel with DIY electronics. Here's a recent one that linked to the Defusable Clock product (for obvious reasons!)http://grathio.com/2012/04/flying-with-homemade-electronics/
You really should not try to take unassembled kit or assembled circuit board in carry on luggage. when they see that on the X-ray you WILL have problems. The assembled circuit board will make TSA freak out. And if you have problems, nootropic design has problems -- our name is on the board.
The best solution is to ship the electronics, not fly with them. Priority Mail International small flat rate box is only $16.95. It's slow, but if you have lead time, that's the way to go. I don't know how to ship it back to the US, though.
Let us know how everything turns out -- or maybe we'll hear about you in the news.
Good luck, friend!