Nice, can't wait to try it :D. Here is the BETA of the mod. Unfortunately I don't have Dawnguard so can't edit Auriel's Bow. But if you want to try it then watch this tutorial:
this is really easy. Just duplicate the bow, select NONE as enchantment, and delete the "MagicDisallowEnchanting" Keyword on the rigth side of the window. That it. Hope you like this mod anyways. http://skyrim.nexusmods.com/mods/27186/