Re: Nema 23 problem
You'll need to peruse the many, many posts on these crappy controllers, unfortunately they are absolute garbage, but some people have sort of got them working, to a certain degree anyway, by re-designing parts of the circuit board.
The TB6560 boards on Ebay are an inferior design poorly implimented, period. They are extremely susceptible to noise, and have a very peculiar power on/off sequence, that will destroy the IC's if deviated from.
I'd suggest run a mile and look at the massmind or Gecko stuff instead. Even if it costs, something that works is cheaper in the long run than something that doesn't.
Another point, without knowing what kit you bought, the steppers may not be usable, depending on the inductance rating. Most of the cheap Ebay kits flog ridiculous high inductance steppers, which require a power supply well in excess of what's supplied. That 48VDC PSU you got is already too high for the driver board, so even if you can somehow get the board going, you'll be limited to 36VDC max, which I'm betting is way too low for the steppers you got with the kit.
The way to work out what power rating your steppers need, is 32 times the square root of the inductance of the stepper = ??VDC.
cheers, Ian
It's rumoured that everytime someone buys a TB6560 based board, an engineer cries!