A marker can be added using the GMarker class; for example, to add a point to the map, I would use something like this:
var point = new GPoint(45.779915302498935, 4.803814888000488); var marker = new GMarker(point); map.addOverlay(marker);
(Of course, you will have to adapt the coordinates to the coordinates of your office, so this does not indicate at some point in France ^^; I believe that the ones you posted should work ;-))
And for the info window, you can use the GMarker.openInfoWindowHhtml method on your marker.
I think something like this should do the trick:
if (GBrowserIsCompatible()) { var map = new GMap2(document.getElementById("map")); map.setCenter(new GLatLng(40.466997, -3.705482), 13); var point = new GPoint(-3.705482, 40.466997); var marker = new GMarker(point);
And the result looks like this:

(source: pascal-martin.fr )
Now it's up to you to build from here ;-)
Pascal martin
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