What HE said!!
I'm not sure why you're posting the key like it's some sort of secret. XTrackCAD is open source freeware, you don't need a special key to register it. Download it and use it, it's free!You might also give this a go:
XTrkCad - Model Railway/Railroad Layout Design Software
Download: Right click on link and save as--
Created By: Sillub Technology
To register, use this free registration key:
Name: Open Registration