Hi,
Chinese motion controller manufacturers, in this case XHC, have a bad reputation for supporting their products.
In many cases, and I suspect applies to this board, is that the company had at one time a talented engineer or group of them whom developed both the hardware
and the plugins. Since then that individual or individuals have departed the scene and now the company manufactures the boards but really have no idea how they
work, and hence their inability to support their products.
I would suggest email the company and get the correct plugin (.dll file). If they can't or won't then throw the board away and never purchase an XHC product ever again.
US and European manufacturers make products that work as advertised and support them. I'd recommend the Ethernet SmoothStepper by Warp9TD, the PoKeys 57CNC
or any of the UC100, UC300 or UC400 by CNCDrive.
Craig