Nice project indeed!
It is possible to convert a MPD to be read by LDD, but (especially since you are new to it) the simplest is to use directly LDraw system (a MPD is a LDraw model file). Install the All in one installer http://www.ldraw.org/article/104.html and open your model with one of the editors provided (LDCad is highly recommended).
It is possible to convert a MPD to be read by LDD, but (especially since you are new to it) the simplest is to use directly LDraw system (a MPD is a LDraw model file). Install the All in one installer http://www.ldraw.org/article/104.html and open your model with one of the editors provided (LDCad is highly recommended).