The Snack Package requires the tcl/tk include files which come Tcl/Tk source distribution and they should be in certain places. (See Snack documentation.)
In addition MusicScribeKit calls upon other shared libraries or dll's for performing the time scale modification of the Snack sound structures. You need to build this library snackext.so (or snackext.dll) after you have compiled the new Snack Package using the software included with the source distribution. For Unix or Linux, I have provided a Makefile; however, you may need to modify it so it points to the right locations of the Tcl/Tk sources and X11 include files on your system.
I have compiled the libraries on both Fedora Linux and Windows (Visual C++ 6.0), but I do not have experience on other systems.
Assuming you can create these libraries and scribe.tcl is able to find these libraries, you are ready to use musicscribekit. (On Unix, you may need to set the environment variable TCLLIBPATH to the folder where libsnackstub is found.) The snackext library is placed in the same folder with scribe.tcl.