Reply to Expanding LEDs ?

Hi there, first post here'

My MF unit has been dispatched and i have started researching the resources for expansions for later if i ever decide to do it. By the looks of it, tutorials aren't far away but i thought i may as well ask.

How many additional LEDS can be added to the MF? And is it difficult to modify the software to give these new LEDS MIDI addresses?

many thanks in advance.
Nick