I have four Pella casement windows installed in a 13 year old home that are beginning to drag to the point that they will not shut far enough for the latch to engage.  My closest Pella dealer is a hundred miles away, so would prefer not to call a dealer for an adjustment.  The windows seem to swivel on a single connecting screw top and bottom.  That must be where to start, but I thought I would run it past you folks first.