1) create a playable infantry unit and name it blu1.
2) create a maker on the map and name it myMarker
3) create a trigger (your choice of how to activate it) with the following in the on act box:
newWP = group blu1 addWaypoint [markerPos myMarker,0]; newWP setWaypointVisible true; newWP setWaypointType "MOVE";
4) begin the game as blu1 and activate the trigger. Observe that no waypoint in created.