LinuxMCE already does boot over network...
All MediaDirectors and Orbiters run directly off the Core.
First, enter the Admin site and press "MediaDirectors" and Press "Setup diskless MD *"
* When you add a new diskless M/D, you must first click this button, wait for the setup process to complete, then do a "quick reload router", and then you can bootup your new diskless media director.
That does not take long, then enable PXE boot in Bios on the PC you want to use as an MediaDirector.
The next step takes a while... With Gigabit network it's not so slow, but with 100mbit it can take 1 - 4hours to build the image.
Use an Orbiter to do the setup, or you will not get the messages you need to answer to get the MD up and running.