Alright, having a pretty annoying problem, and it seems I'm the only one to have this problem.
Got my CNC running great for the most part, but the if ran too slowly, around .8 IPM or less, steppers go into standbye, as if getting no commands. Basically on slight diagonal angles and slow curves, the slower axis will stop and lose steps. I'm running the gecko g540 on a 48v 7.3 amp PSU, pushing three 3.5 amp steppers, at 20,000 steps per inch.
I just wish Mach3 had a minimum speed setting.
Anyone have any suggestions?