Check your wiring against the ports and pins display in Mach3 and the Gecko manual. Did you get an XML file to use? Does it come up when you run Machloader? Make sure you've got an e-stop wired in, since that's on by default in Mach, and it won't come out of reset until it sees that signal.
Doesn't Keling give you any help in setting up their kits? Since you're using their system, they should be your first line of support.
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