I found this awesome how-to on how to remaster Knoppix while in KDE. My only problem is that I can't get KDE to start. I get this error:

The following installation problem was detected while trying to start KDE:

Writing to the temp directory (/tmp) failed with the error 'Permission Denied'.

KDE is unable to start.
can't create /tmp/mcop-knoppix (Permission denied)
Does anyone know how I can fix this error? The tutorial doesn't explain what to do when this comes up.