The Absolute Overlay function charts a selected price file and overlays it on your currently displayed chart, unchanged and without re-scaling.
To Overlay an Absolute price line on a graph:
-or-
·Click on the Add Overlay icon

From the displayed dialog box

NOTICE
The Synchronise Date field is not active, this is because this data is not necessary for the absolute overlay calculations. It becomes active for the rebased and relative overlays