[urlname] allows you to use the "name" portion of the HTML anchor tag. This is for more advanced users and works excellently for any guide posted on Southperry.
Click here to see all jewels from Item Maker
And here's what the code looks like on the Item Maker guide --> [urlname="Jewels"][/urlname]
vBulletin expects that the [url] tag is an actual link and not a name reference. So if you try to do [url="#C3"] with [urlname="C3"], it won't work. This is a limitation of vBulletin. I'll probably have to do some code digging to find out where to fix this.