i had a really strange problem with the day/week calendar view on our windows 7 notebooks, that when they scroll down, the appointments get not right flushed away, that means a appointment where x-times there.
but it was only a view problem, when they changed to another day and back, it was all normal, until the scrolled again, but only i a appointment gets marked.

so it is a Aero-Display problem.
when you disable the "Desktopgestaltung aktivieren" (sorry, i dont know this in english) in the Kompatibilty register on Setting of the Programm-Link it works fine.

Look at this, unfortunately also in German:


Hope that solved also a lot of problems for other users...