I am not using the charge pump feature, I had issues at the time and never went back to diagnose. Never had any more issues.
I am also not using the lms spindle kit for the sx-3, I spoke with lms and my particular machine had some differences then the others. Could not get it to work. Now that I'm reading this post it looks like now they offer a new chip . I decided to go with the x4 spindle kit 5000 rpm motor, New face plate, and Spindle board. Also installed new ceramic bearings and had a 45 tooth htd 5 pulley made to match the spindle pulley. Currently got it it running on manual mode and am working on wiring the cnc part. X4 spindle board uses PWM 0-10v.