Download the manual from Tormach. It'll tell you how to adjust backlash, which starts with inspecting for it, plus the other inspection points around squareness of Z, X & Y. If they'll let you, pop the way covers off and check the Z and Y ways.
"Fried ATC board" could mean anything from you need another $100 board, to the entire ATC electronics are toast, and you don't really have a way to tell without replacing the board, so pay accordingly. Look up under the umbrella to see if the forks still have their black plastic bolts holding them on. They're annoying to replace so people doing production sometimes swap them for steel bolts, which is fine until they crash it, but the screws are supposed to be a protective weak-link.
All that said, even a beater machine can make decent parts if you are realistic about the machine's capabilities and wear..