I have this problem, and i need to now if someone else have the same or have found any solution. I have a tip 0.5 diameter and lengh 3mm. when i go for the calibration, the default routine does not can run, because when goes for the level points it hit the stem and not the tip cause of the small length. i try some things like 3d calibration where i set 25 points and 4 levels, but then the calibration is exceeded the limits.
you need to change the start/end angles of the calibration so it doesn't try to go as far down the side of the cal-sphere. OR, get a smaller cal-sphere. I have head of people using a LARGE probe (say, 6mm) as the cal-sphere for tiny probes instead of buying a small sphere.