TygerCub, I had the same exact problem and a kind soul - Sharen from Sams3D - took pity and gave me a workaround to the problem you're having. When you try to select or deselect and find that you can't just open the date and time properties box and then with that open try again and it will work! At least it does for Sharen and me, both in Poser 4 and Poser 5. I have no idea why :)