Various X errors (difficult to see)

[Luca Presotto]

Hi,
I have a freebsd 7.0 release with xorg 7.3 installed on a i386 with a
NVIDIA GeForce Go 7300
Official nvidia drivers installed and apparently no problems.
In the xorg.0.log file there aren't any errors, glx is correctly loaded
etc..
My system starts without X and then I use startx to start X server and
KDE3.5 (if I'm not wrong about the version).
Some errors are written on the console and I'm not able to see them!
To see them I have to stop X (with ctrl+ bkspc) and use scroll lock to
see what's there.
I found the console full of "X error: bad window parameter" (and some
numbers and parameters which I can't remember)
Then I find a lots of warnings about kde problems (about loading arts
daemons). 
Except for these errors that I wouldn't be seeing if logging in directly
in a graphical environment everything seems to work fine.
So I have some questions: is this way of reporting errors correct?
Can this be the related to the fact that when I try to use compiz-fusion
it starts but it's way too slow and uses a lot of cpu?
Should I worry about these errors?
How can I solve them?? (They seem really too generic)

Thank you!