i'm working my way through this myself, the only help i have found is through online support at vero.
my part is more of a pulley with fins then a true impeller but that is the cycle i'm using and i have got path worked out for the blades and the hub using the multi blade machining choice for roughing and finishing.
i'm using regular endmills to rough and a tapered ballnose endmill for finishing
are you still stuck? is there a particular thing that stumped you?