It sound like you have the drivers installed, so it's unclear why you can't make the Aggregate Device.
Presumably Eventide Dice is the same as Eventide H8000. The names seem to change with every new version of the driver – don't know why,
You'll have to make routing changes to get FireWire sound through the unit – are you sure this is set up OK ?
It's always a mystery to me that sometimes you have to restart and sometimes you don't.
