How to completely uninstall Drive Genius, OS-X 10.6.8

Question

Mac Pro running OS-X 10.6.8.
In February 2012 I purchased Drive Genius 3.1.1 from Other World Computing. Tried it. Not much use to me, so I forgot about it.
In September 2014 I "upgraded" to Drive Genius v.3.2.5 but it would not run on my machine, so I forgot about it.
At some later time I realized that the computer was not going to sleep despite the System Preference setting. I could put it to sleep manually.
I inquired on the net why this was happening and serendipitously found complaints about Drive Genius being very difficult to un-install.
I looked at the Console logs and saw this pattern, repeated every 10 seconds:
Jan  2 10:18:09 MacPro com.apple.launchd.peruser.501[124] (com.prosofteng.DGMonitor[898]): posix_spawn("/Library/Application Support/DriveGenius/DGAgent.app/Contents/MacOS/DGAgent", ...): No such file or directory
Jan  2 10:18:09 MacPro com.apple.launchd.peruser.501[124] (com.prosofteng.DGMonitor[898]): Exited with exit code: 1
Jan  2 10:18:09 MacPro com.apple.launchd.peruser.501[124] (com.prosofteng.DGMonitor): Throttling respawn: Will start in 10 seconds
Jan  2 10:18:19 MacPro com.apple.launchd.peruser.501[124] (com.prosofteng.DGMonitor[917]): posix_spawn("/Library/Application Support/DriveGenius/DGAgent.app/Contents/MacOS/DGAgent", ...): No such file or directory
Jan  2 10:18:19 MacPro com.apple.launchd.peruser.501[124] (com.prosofteng.DGMonitor[917]): Exited with exit code: 1
Jan  2 10:18:19 MacPro com.apple.launchd.peruser.501[124] (com.prosofteng.DGMonitor): Throttling respawn: Will start in 10 seconds
etc. etc. apparently willing to go on forever.
I tried removing every trace of Drive Genius including in:
/Library/Application Support/DriveGenius (folder)
/Applications/Drive Genius 3.app (icon)
/Users/Library/Application Support/DriveGenius (folder)
/Users/Library/Preferences/com.prosofteng.DriveGenius2.plist (file)
/Users/Library/Preferences/com.prosofteng.DGAgent.plist (file)
~/Library/LaunchDaemons/com.prosofteng.DriveGenius.locum
~/Library/PrivilegedHelperTools/com.prosofteng.DriveGenius.locum
I even downloaded and installed the OSX 10.6.8 Combo Updater.
But, the every-ten-seconds" events are still happening.
How can I get rid of this thing -- whether or not it is the cause of the failure to go to sleep?

Answer 1

After a lot more work, the "repeated-every-10-seconds" messages seem to be gone now.
To review, I already deleted these folders and files:
     /Library/Application Support/DriveGenius
     /Applications/Drive Genius 3.app
     /Users/Library/Application Support/DriveGenius
     /Users/Library/Preferences/com.prosofteng.DriveGenius2.plist
     /Users/Library/Preferences/com.prosofteng.DGAgent.plist
I found this file and tried to remove it:
     /Users/jimp/Library/LaunchAgents/com.prosofteng.DGMonitor.plist
Dragging the file to the trash did not work. Trying to remove the file via the Terminal "rm" command did not work. Even doing
"sudo rm com.prosofteng.DGMonitor.plist" would not work, resulting in the message:
"rm: com.prosofteng.DGMonitor.plist: Operation not permitted" and the file was still there.
I used COMMAND-I to change the file permission to READ AND WRITE and then used the VI editor in Terminal to "comment out" every line of the file by adding a "#" at the start of each line. Then I wrote out the file.
I still could not remove the file---I don't know why--- but I suppose it is now inert and can't do anything.
Upon restarting, the Console log no longer shows those "every-10-seconds" errors.
I assume my problem is solved?
I have yet to determine whether the Mac Pro will go to sleep as it used to do.
Now I need to remember to NEVER TRY INSTALLING DRIVE GENIUS or other dangerous applications again.
I hope these notes are of some value to other Mac 10.6.8 users out there.