It's not doing that for me... Can you see the red spots at all? (the fact you mention them suggests you can sometimes?). The bit that was catching me out was - well once you can see the red spots, make sure you've selected the bottom icon (the one like the dotted line outline of a rectangle) and then press ALT and drag your cursor over the map to make your selection (ie to include the red spots you want). Then when you let go of the mouse button, the details of the sites will come up in the left hand side.