TkTurf is distributed under the GNU General Public License. All terms and conditions specified therein apply. Furthermore, by running this program you explicitly agree to the transfer to it of all permissions owned by you to read and/or affect any data on the system(s) in question, as well as potentially distributing any information gleaned from this system.
Furthermore, you transfer all permissions granted in the previous paragraph to any plugins you may download and install, especially the release from damage included in the GNU Public License.
If you wish to modify, or, particularly, to improve upon TkTurf, note that you must abide by the terms of the GPL, but furthermore I would ask that you send all changes to firstname.lastname@example.org so that TkTurf can be cooperatively improved for the benefit of all users of it or derived works.