First time CNC electronics woes

[endgrainguy]

I just finished wiring my woodworking CNC router, and I'm having lots of problems with electronics. Often getting stuck in E-Stop mode. Z axis delivers only much slower speed than I expected and want, and z stepper grumbles even when not moving. All I"ve done so far is tune motors and jog them around a bit.
I did a sloppy job wiring my controller box. Could this be part or all of the problem? I used these steppers and drivers http://cgi.ebay.com/Stepper-motor-64...742.m153.l1262
with power supplies from same vendor, and this breakout board http://cgi.ebay.com/CNC-Emergency-St...742.m153.l1262.
Machine uses high quality mostly used components - THK rails and ball screws mostly, sturdy 80/20 frame.
Z axis weighs about 20 pounds, largely because of a mounting sysyem that allows me to run spindle horizontally or vertically or anything imbetween.Z axis uses a fine pitch 2mm lead THK ball screw. Can I only expect about 20 feet/minute from this with a 640 oz/inch stepper? Since I want to use this mostly with spindle horizontally to cut dovetails and the like, a faster speed would be really nice on the z. The x and Y have no problem zooming around at 300 inches/minute. Its a fixed gantry, moving table set up.
And what are the likely causes of my getting stuck in e-stop mode?