Does your KDE desktop effects work okay? Do/can the desktops switch using the cube effect etc?
There are some quite nice effects using the KDE desktop settings, but not (yet) as nice as Compiz (IMO

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Have set your window manager to Compiz? (Configure Your Desktop >> Personal >> Default Applications > Window Manager)
Hi: The answer is a resounding YES to all of the Kwin-related stuff above. But, I simply can't run Compiz on this machine ... weird. And, BTW, it won't let me select Compiz as my default window manager.