I actually figured out how to do this... it wasn't the tool, it was windows not making the partition correctly...
follow the instructions on this forum post (with the tool) as well as this one to create the partitions: Using a USB3 Drobo with an Xbox One as External Storage
@angerwound, I've been trying to get a 4 bay drobo to work with this app, and have had limited success. When you actually format the drobo with the xbox one, it crashes, and gets very angry. I've successfuly managed to use your app to get the drobo to show up on the One, but only if I create...