Is there a correct size still to bring to the time line. I have read in other video editing programs that major stalls in rendering can occur if stills are too big. This is a concern for SD time lines as well. You usually want a still big enought to move around on (zoom / pan) and to have room for transitions . If the out put is going to be HD 1920 x 1080 frame size is that a good size for a still or is there some max or min size or ???