cvs -z3 -d:pserver:firstname.lastname@example.org:/cvsroot/logicaldesktop checkout logicaldesktop
This will create a directory called logicaldesktop in your current dir, and put the source code in it. If that does not work, simply try again, SF sometimes behaves strange.
Then, periodically, to keep your version on par with the current version, enter the directory logicaldesktop and type:
cvs update -dPand your local version will get updated.
Alternatively, you can get the latest snapshot (.tgz).
You can also browse the source code online with sourceforge: simply click here.
Before running the program, read the instructions in the file README.