I have no clue about the Digi you have but here's the setup page from guitargeek.com .

http://guitargeek.com/rigview/119/

Hopefully your fx box has some of what he's using and you can get the sounds you want. Try to keep in mind that tone comes from your fingers as much as it does from your equipment. the people you wanna sound like are notorious for their HOURS and HOURS of relentless practice...
btw.. here's Yngwie
http://guitargeek.com/rigview/259/
and here's Satriani
http://guitargeek.com/rigview/293/