Hello,
I found a bug in GetLineOnALine() method in MapSuite 6.0.0.157. It returns the line segment to the position of the nearest vertex to a given point on the line and not the segment to the given point itself. In MapSuite 6.0.0.77 everything worked all right (Upper Screenshot).
I have attached my sample application where you can reproduce issue.
Thomas
GISWpfSample_GetLineOnALine.zip (21.3 KB)