It should not be that difficult …
The Card supports up to 4 screens natively, after that you would need active adapters for the screens. This you have in the MS Hub (is an active device) so as long as the HDMI Cables you use are not longer than something like 3 meters that should be fine.
Just connect the screens 1 by 1, make sure they are in the correct resolution and frequency in windows (with didgital screens normally goes automatic). When done go to Crimson driver and create Eyefinity Group. Please do check positioning of the screen, because you cannot make all combinations … please check here: http://www.club-3d.com/index.php/technology/amd-eyefinity.en.html