Remarks

To avoid negative coordinates, you can specify a FalseEasting that will be added to each projected x coordinate. The Krovak projection is a little unusual, though. The point whose projected coordinates are (FalseEasting, FalseNorthing) does not have the geographic coordinates (CentralLongitude, CentralLatitude). Instead, it is located at the apex of the oblique cone, so its longitude is CentralLongitude but its latitude is approximately 90° - ColatitudeConeAxis.