i think i know what u mean....i'm pretty tired, so don't blame me if i'm talking a load of crap ^_^
Edit the header template, add this around where the buttons are
Code:
<a href="proarcade.php?s=$session[sessionhash]"><img src="{imagesfolder}/top_arcade.gif" alt="Home" border="0"></a>
then upload the arcade button to the folder where your images for that style are located