XTrackCAD for LINUX is shipped as a self-extracting archive (executable).
./xtrkcad-setup-4.2.3b.i386.sh --prefix=/usr/local --exclude-subdir
xtrkcad
will be created in /usr/local/share and all files will be unpacked into it.
If you install XTrackCAD into another directory, set the XTRKCADLIB
environment variable to point to that directory.