Press spacebar to page down. I think it's shift+space to page up. It's way easier. You can clean the track ball, there are guides for it online. Part of the reason I chose the Curve 8900 over the Bold 9000 is the new trackball socket that's tighter and less likely to get dirty. My trackball is still fine after 2 months, 1 month in the sleeve, 1 month with no sleeve and just a rubbery skin.