You will have to look and see which pins you have to which drive, its not a generic thing, it can be set up to use any of the output pins. It will more than likely be
x step 2 dir 3
y step 4 dir5
z step 6 dir 7
As for the limits you dont actually need seperate home switches, I just have one optical switch for each axis and they act as + and - limits, then when a home is done mach will use them as home switches.
What kind of switches do you have? is this a bought setup or are you making the control up yourself?
Will check out your site in a wee while.
Hood