Hi,
I would like to achieve exactly the same result and I found your post extremely useful to me. Thank you!
I have an Arduino Leonardo (Olimexino) and I've just ordered the same USB HOST shield V2. Hope the header pinout doesn't require any modification. Do you need to connect the ICSP too?
My question is about the power: does it work with 5V or 3.3V? I would like to make both of them working with 5V.