TKE has excellent documentation. However, it is a little bit tricky to install it on Ubuntu, because of some dependencies. To install the dependencies on Ubuntu, run:
sudo apt-get install tcl8.5 tk8.5 tclx8.4 tcllib tklib
Now, just follow the installation instructions in the TKE documentation. And remember to run the installation command with
sudo. I installed to
/usr/local without any problems.