Unable to Select Objects or Draw on Screen

The situation where objects cannot be selected or drawing cannot be done on the screen is usually caused by a zero-length or zero-width element being drawn. While in mouse selection mode, click on an element drawn on the screen to try to select it. If selection is not possible, since a zero-length element is likely selected, press the Delete key (Del on keyboard or Delete button on program screen) to delete the faulty element.

Continue left-clicking and then pressing the Del (Delete) key until the element you click on becomes selectable. If necessary, continue the process on other floors where the problem exists. If selection becomes possible in mouse selection mode, the problem is resolved.