Composite manager causes graphic gliches

[Yogiz]

Well, I think I should bring the thread back to life as I shortly have
more time in my hands then before to deal with the problem.

As I understood from you responses, eighter fglrx driver or XRender is
the thing to blame.

Could you suggest how I should proceed? Any logs that I should check to
clear up the problem, any options I should experiment with? I really
like xfce's composite and I'm pretty hellbent to get it to work once
and for all.

Thanks in advance, again.