I wouldn't just dismiss it when the green LED is on. I just had to send one back to Gecko because it would not work with the green led lit. I did all the usual everything swapping, testing, checking...
The trouble always followed the gecko. I finally pulled out a 201 from my other controller, hooked it up and got the machine running again. I did have to run the 5VDC to the 201 instead of ground.
I now have two new Gecko 203's that arrived for my lathe project coming up, so I can get the gecko's back where they belong. I haven't heard back about what the issue is with the lazuy one I sent back, but should hear something after the Holidays.
There is also a troubleshooting guide for the 203V's in the Yahoo group files section. I found that very helpful. You will have to be a member there though. Easy enough to join.
I would also suggest you look at the Mach 3 troubleshooting video.
http://www.machsupport.com/Videos/Mach3%20Video%20Selections/Mach3%20Video%20Selections.htmlThat may also help you pinpoint the trouble. Your resistor sounds about right for Keling 425's. They are 2.8 amp on BP IIRC.
Also you said you have X enabled. Check out this other Mach video.
http://www.machsupport.com/Videos/Mach3%20Video%20Selections/Mach3%20Video%20Selections.htmlIt deals with inputs and outputs.
In the config, ports and pins section, under motor you should have the step and direction pins assigned like you have them setup on the BOB and you should make sure that the port number on the right is calling the right port. Step should be active high and direction either way depending on which way you axis travels. It can be reversed by switching that.