the osCsid and cPath are two entirely seperate issues.
cPath
To remove the cPath querystring got to admin>SEO URLs>Add category parent to begining of URLs?
And set to false
osCsid
The osCsid must be attached to the querystring on first visit to maintain a session state, after the first one or two clicks it should disappear, if it doesn't then you have issues with your includes/configure.php file.