To move the attachment point of a referenced floor plan drawing

The referenced floor plan drawing reference point is not the intersection of the X and Y grid lines. The reference point needs to be moved.
Press Pick in the Reference Point settings group.
A target cell appears at the floor plan’s attachment point and another is attached to the pointer. Enter a data point at the intersection of the grid lines to establish the new reference point.
Press Apply.
The drawing reference point is moved.
Start tracing rooms over the referenced floor plan drawing.