Boxwood is an extremely hard and dense wood that machines quite well, holding very high levels of detail. It usually comes in the form of miniature logs. I'm not sure what you mean by a "skimming tool", but if I wanted to make flat boards out of a piece I would use a saw first, splitting the log into two half-cylinders, and then cut those lengthwise into parallel strips. I suppose you could surface them on your CNC router, if you had a way to hold onto them while you're doing that, but it would be quicker if you used a jointer on one side and then a planer on the other.
If you are machining it, I'd think you can take heavier cuts than .10 mm at a time - a whole millimeter shouldn't be a problem, going at 2000 mm/min or so.