Output to an entire port

  1. Buy a FEZ Mini and replace it with a Cerb40 later.
    http://www.ghielectronics.com/catalog/product/134

That’s quite unlikely, since Oberon’s port, which is the basis of GHI’s port, was for 4.2. If a 4.1 port was produced, I would expect it to take longer to stabilize than the 4.2 port.

Not enough legs on a mini.

Why not use the registers directly by using the Register class? Should be possible to do your thing with those!

No Register class on cerb direct register manipulation through RLP Light - yes.

Design a board based on USBizi100… you can expose exactly the pins you need, and make it exactly the size you want.