Help with Xml Menu

I downloaded the XML Menu v3 and did some basic editing (just visual things not in the sourcecode) to fit my website. I’m having trouble now with a “mouseover” action i´m trying to do.

I can´t manage to find the path (_root.menu.etc.etc) of the dynamic textfield inside the “item” “sub” and “subsub” items in the actionscript to detect the textfield’s width or character number to make the underline fit the word above it.

I was wondering if anyone could help on this.
hope i made myself clear.
sorry for my english.
thanks a lot.

ps. the files are attached