Ha, time travel, and humanity? If we can't even mix the general population with intelligence, what hope is there for us being able to time travel?
Actually, with our most intelligent minds, we may be able to invent time travel among other things, but who says we'll be able to control it all that well.
Besides that, a basic principal of time travel is to fold the present into the past, understanding the 10 dimensional theory helps for beginners. (Also, knowledge of string theory would be helpful).
If there is a way to travel through time to a specific point, I would go back to the medieval ages, though, I'd bring a few things with me.
Anywho... if my intelligence actually kicks in, I'd probably destroy the device as well as the plans and notes. Oh, can't forget the people either, things that bend the rules are dangerous, this applies with people in games too.