An obscene gesture from the engineer of a train is one of the controversies surrounding this weekend’s Quad Cities Marathon. Organizers of this weekend’s Quad Cities Marathon will file a complaint with the Iowa Interstate Railroad today because a train blocked the path of several front-place runners for about five minutes. The delay kept one runner from qualifying for the Boston Marathon. Race organizers had talked with railroad officials and thought they had the train’s timing worked out. The engineer of the trouble-making train reportedly made an obscene gesture as he passed by the waiting runners.