Found the problem. I just didn't understand how the VFD actually works. First of all, I am not using a VFD. I am using the gecko VFD to control an SCR, wich in turn, heats up my hotwire. I thought that the 0-10VDC just came out of the G540. I called gecko and they explained that the voltage on the VFD circuit has to come from somewhere else. e.g. to test if VFD is working... connect the negative side of a 9volt battery to pin 7 on the gecko. connect the positive side of that battery to pin 9 (VFD +10VDC), then connect a voltmeter to pins 7 and 8. Basically the gecko takes in 10volts on pin 9, and releases 0-10 volts on pin 8. Really, it just acts as an electronic potentiometer. So if you set up a spindle pully in mach3 to have 0-100 rpm, and you set the rpm to 50 and turn on the spindle, you should see half of the 9-volt battery charge come out of pin 8 (with 7 as ground).
In my case, I got rid of the 9-volt batter and grabbed an old ac/dc converter in the back room and used it.
Everything works beautifully now.