how to use extracellular mechanisms

[luckychild]

Hi NEURON folks.
I'm a new Neuron user. I'm working with the 6.0.4 version of Neuron on Windows XP.
I have used Maxwell, which is a finite element software for calculation of static electric field, to calculate the electric field distribution in spinal cord, and want to employ such numerical results (voltage values) to simulate the responds in nerve cells. I think extracellular mechanisms are available for me. I have read explanation about this instruction in The Programmer's Reference documentation, relative discussion on our forum and programs named extcab*.hoc. I, however, stiil have some questions as following
(1) I have read some papers about model of myelinated fiber. Such as “Johannes J. Struijk, Jan Holsheimer, Gerlof G. van der Heide, Herman B. K. Boom, Recruitment of dorsal column fibers in the spinal cord stimulation: influence of collateral branching. IEEE Trans. on Biomedical Engineering, 1992, 39(9):903-912â€