Comment on Mail Unread Menu

This is a disaster on leopard 10.5.4. After I installed it on my machine, the icon disapeared but was still running in activity monitor, and then this morning my mail app was buggered and had to delete the .com.apple.mail file. Someone else installed it on their machine at the same time as me and they had the exact same problem with mail, as well as their whole screen turning into blocks of colour. Proceed with caution