"Other thing is I can't find much information about OSX supporting SB  Live, don't want it disabling the onboard sound will keep looking into  that :-("
Don't worry, OSX doesn't support the Soundblaster card. It will be ignored when you boot OSX. And under MorphOS you have to configure it before it will work.
Also, if you want more USB ports, buy an NEC based USB2.0 PCI card (they're about $5 on Ebay).