Thought I would post this rather obvious hint, but it may be useful to others.
The default way that the new Plotmaker auto-numbers drawings is similar to how it does sheets - the order the drawings are placed in the list as seen in the Navigator determines the drawing number. This is inconsistent with the U.S. National CAD Standards that uses a "grid" system combining letters designating vertical location and numbers for the horizontal.
Unfortunately, Graphisoft hasn't developed a way to automatically give a drawing number based on layout location. To give your drawing a correct NCS identifier, select the drawing and go to Drawing Settings (CMD-T on Mac, ALT-T on PC). In the Identification tab, select the Custom option and enter your letter/number combination based on where the drawing is placed on the page. This custom number
