Problem with VR integrity

[Asoklinchen]

Hello, I did a tutorial to convert this script in order to have VR integrity: https://www.youtube.com/playlist?list=PLrk7hDwk64-bXSWcXHR-0zLVMMsMtu0ad

For some reason I get these errors when in creation mode to save gestures:

The mentioned error is in line 71 of the PDollar Geometry script.

public static float SqrEuclideanDistance(Point a, Point b) { return (a.X - b.X) * (a.X - b.X) + (a.Y - b.Y) * (a.Y - b.Y); }

An answer is appreciated. :D