Just connected a new computer and installed 3-6-46 (which is what I need for my PRTAlpha). Connection went fine (which is unusual for me), but everything Freezes up when I try to C3, C2 or JH. I can MH, move the gantry with either the J or M command, or us the K command to move. I have to totally shut the computer off and restart. I have installed firmware. Am I missing something obvious? Any help appreciated.