FCKEditor which connector to use?

Hi-
I am getting the xml server error 500 everytime i try to use the Image Uploader File Browser.
I think my paths are correct in the connector files, i tried with the config.asp and now i am trying with the config.php file (designated in fckconfig.js file)
I can't get rid of this error, not sure which connector to be using, i am about to give up and go with Mambo.
Could there be a permissions problem? Help??
Any ideas or help?
Thanks in advance-