Just throwing this out there, but it seems that keytouch wont build from outside of the source tree. For example, if I do this:
tar -xzf keytouch-2.4.1.tar-gz
then the scripts will create the path tree in $BUILD_DIR and put all of the Makefiles in the tree it just created. It will then try to build from those makefiles, except they don't know where the source files are in this tree, so the build fails.
While I don't particularly mind, I know a lot of people think it's bad form to "contaminate" the source tree by building a program in it.
I just thought I'd point that out in case anyone cares.