the start button you are talking about comes in two sections, the actual startbutton, and the 'glow'
do you use skin studio 6 or skin studio 5?
this is how i do the startbutton you talk about.
first i get the startbutton and glow image and copy and paste them on a new blank canvas, so they are "one" and match up so I see the whole image, then i take it to photoshop and do my artwork on it to how i want it.
Then I go back to serif (an art program) and start rubbing out the startbutton, leaving only the glow on the edges (i do this by first taking the original glow and comparing it to the new buttons i made, and measure so i know where to rub out) after the rubbing out is done, i save this as the glow part of the button, then i do the opposite , rub out the glow and leave only the startbutton part....then save it as the startbutton. (this method is probably totally backwards, but its how i work.. and it works for me)
in the start button section for either skin studio 6 or 5, there will be a 'glow' section where you can apply the glow and in skinstudio 6 under the startbutton section, if you click on the extras tab, the first option lets you "always show startbutton glow' and you have to check that so it shows up on your skin.
I hope this has helped you somewhat K..........
you can always pm me if you need more help, I am always more than happy to help.