Actually I've gone ahead and worked on it myself, in order to make it compatible with a grid layout (which was the more general problem I was trying to solve).

Actually I've gone ahead and worked on it myself, in order to make it compatible with a grid layout (which was the more general problem I was trying to solve). I still need to clean up my modifications, but I should have a pull-request out within the next day or two, adding 'grid' to the existing 'horizontal' and 'vertical' direction options :)