Seem to be following the instructions/directions ok. On the Add tab, selecting video; locating and tagging the appropriate .mov file (which brings doc name and location to right side of screen; clicking on NEXT; selecting the Format "MOV" from the list (screen pop with MOV quality selections and Settings on it: FFmpeg Arguments field has an autofill value starting with -s and the quality I selected); clicking on NEXT; clicking on CONVERT. Almost immediately, there is a gold error triangle with exclamation point inside. When I move my mouse over the triangle, there is the location and name of the .mov file and then "Invalid argument". Any clue as to what I'm doing wrong or neglecting to do? Thanks.