Hi. "kdesu" and "gksu" seem to be directories which need to added to the path along which some needed files can be found.
For the best help on this matter, I suggest calling up a Linux guru who can help you add the required directories to your path.
Here's a URL which can help: http://www.troubleshooters.com/linux/prepostpath.htm.
I suggest following the directions in the section titled "Adding to All Users' Paths (except root)." I'm pretty sure you need to be logged in as root to do that, so it's best to have someone help you with that, unless you're fully comfortable being the root user.
For clues on how to find kdesu and gksu, you can try:
1. locate --updatedb
2. locate kdesu
3. locate gksu
The locate command will display long strings ending in kdesu and gksu, beginning at the root, which is " / "
At the end of your present path, just add a colon " : " no spaces, and then after the colon, add the long path to kdesu and gksu, including the initial slash character.