Before attempting to run any of the Future Lab Tcl applications, make sure you are aware of the tcl source directory structure.
You should then edit each main application source file and set the variable TCLDIR (which should be the first non-comment line in the program) to point to the source directory tree (eg: /home/rick/tcl/code) where you have installed the Future Lab Tcl package. Make sure the path you use points to a directory and does not end in a forward slash. Note that the forward slash should always be used as the path separator even in the Windows and Mac operating systems.
Since Tcl does not compile to native machine code, you will need a runtime environment in order to run the Future Lab Tcl applications. You may either install the full development version of Tcl or install and use the Freewrap runtime kit. The choice of which type of Tcl to install and use depends on whether you will be doing any Tcl development. If you plan on developing Tcl code, you should install the full development version.
If you decide to install Freewrap, make sure you copy the main Freewrap binary/executable to another file (I generally use the name tclaunch). The action causes Freewrap to act as a stand-alone Wish interpreter. You can then launch the Tcl applications using tclaunch. Refer to the Freewrap howto for details.