if you read the instructions for the original x-carve you will notice that the spindle is a 24 volt spindle, as such I can see why you could not get it to work with the 0-10 volt and ground as also with the Pulse width modulation signal.
as per the directions it should be wired into the original controller 24 volt at the power supply
http://x-carve-instructions.inventables.com/xcarve2015/step14/
you will need to connect this to a 24 volt supply voltage somewhere or somehow to the newer x controller. But per the instructions for the new x-controller Note: NEVER hook a spindle directly up to the X-Controller. These are only control signals, NOT power.
Spindle Control
For all AC spindles, you can use the PWM signal from the X-Controller to activate a relay to turn the spindle on and off. When going through the machine setup, select the Dewalt 611 and the max RPM will be set to 1. The PWM signal will now act like a simple enable on/off output.
For DC spindles such as the 300W Quiet Cut spindle, you’ll need to wire the PWM signal and GND to the spindle speed controller PWM screw terminals. Make sure you move the jumper on the speed controller to the right position, closest to the PWM screw terminals. Go through the Easel machine setup, clicking on “Other” and set your Max RPM to 12000 (this may be different for other DC Spindles). Wiring diagrams will be added shortly to help with clarification.