i had quit maplestory for over a year

so they sent me an email saying that i have untouched 17k NX on my account that now they will be expired if i dont use them

so my question is

if i just buy an NX item, but dont put them in my character or w/e, do they expire?

and how much NX does it cost to change server/channel/world

like Nova to Scania

Not sure on the first one, but they just had world transfer for 1 nx. They removed it after that although I'm sure they'll bring it back at some point.