The templates will give you the beginning of the yard, where to place you tracks, so build from there, that's what I do, imagination its called, reason why I play Trainz.
Go to my website and take a look at the screenshots there, some were taken in Surveyor of a few yards, the layout is undergoing an a major reconstruction so its not finished yet.
http://members.westnet.com.au/nightcrawler/trainz/index.htm
Needs updating too...