There's a bug between the Grid (2nd monitor) and Navigator. If I hover the thumbnails in the grid, Navigator will show the last image I hovered and not the current one that is selected. Also, it won't show preset preview if I select the image by the grid.
So basically, hovering, selecting and picking the images in the Grid messes the view in Navigator. Filmstrip is working fine.
It was already mentioned and documented during the beta phase but wasn't fixed:
http://forums.adobe.com/thread/948447
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