I am running the 4.6.1 on an XP Pro with 4 gig of memory and lots of free space. I am sorting about 10,000 pictures from a skating competition and moving them into folders for Customer orders. Sometimes when I select photos - e.g. 100 - and press control-y then next window pops up right away. The next time I try, it could take 30 seconds to respond. Also, it seems when I select a menu item nothing happens, but I can double click on a thumbnail and have it enlarge.
My guess would be something in the cache???
Trying to sort through these many photos with this delay is painful....
Kevin