I came across this article today. It's a 2010 article on MMN from the European Neurological Journal.

It's technical in places but gives a good summary of the nature of MMN, the process used to diagnose it, treatment options, and a descritpion of research and history of MMN.

It has 104 other articles referenced, so it should give you a starting point to find out more about specific things related to this disease.

It had one thing in it that I had never heard before.

It said that the weakness is not simply due to the demylenation of the nerves cells, but may alter the ability of the nerve cells (axons) to transmit and receive signals.