Did anybody have any luck opening the file?
Opens fine here. There is a difference between what you provided as an NC and what the CAMbam provides as a dxf relative to how big the lettering is.
It is not 3/16" high. May want to try both CV and exact stop as velocity modes. Assume the machine can accurately position for 0.00025 depth of cuts. May want to see how the axis works at .005 feed rate. I don't recall the slowest feed rate i have ever tried but i know there was a bottom limit where my steppers would run well.
Remember that if your starting the plunge at say .010" it will take you 2 minutes to get to the top of the stock surface.
RICH