Some days ago I stumbled upon a nifty xNormal Blender addon from the user ohsnapitsjoel over at BA forums.
The addon is a big time saver since it lets you access all the relevant xNormal baking options directly from Blender.
Blenderartists Thread: http://blenderartists.org/forum/showthread.php?291665-AddOn-xNormal-3-18-1-import-export-Updated-7-6-13
Bitbucket Link: https://bitbucket.org/ohsnapitsjoel/io_xnormal/src
With the latest update there was also added an option to specify a mesh from your .blend file as a cage for baking.