I've been using CS2 Photoshop 9 for some time on an iMac running 10.4.11. all of a sudden, the Layers window will not stay open. It'll open with F7 but as soon as I click on the image I'm working on, the Layers window closes! All the other windows seem to work OK. Did I mistakenly hit something to cause this to happen? It's almost like an automatic window closer. Help please! I can't work with the application with this.