General CNC i-Carver

I've just taken over partial duties in the woodshop at my school and we have an older General CNC i-Carver machine. Have used it a few times and works great. This week when it was calibrating to home position upon startup it froze while trying to adjust the Z position. Tried restarting it a few times with the same result. Sounds like it was trying to engage the motor but the screw wasn't engaging. I left it for 1/2 hour, hoping it would sort itself out, which it did....but overcompensated and drove the carver as far down as it would go in the Z (read embedded cutting tool into frame of machine).

At this point it is stuck, will not budge at all.

Anyone with a similar experience??? Any advice is welcome!