Well, with a 4mm diameter tool you are always going to produce 2mm radii for these cuts.
Additionally, the robot is by default blending motions to keep a - ideally - constant speed. If you want the robot not to blend motions, right-click a movement component (e.g. LIN) and go to Movement Interpolation and select "No Interpolation".
Note that the robot will then briefly stop at every position, so that strategy is not ideal for curves.