Files for all Releases are available here. Here are files for latest Release 201204:

Windows

Executable version 201204.

Linux

Binary package for Debian testing.

This binary package has dependencies on libqtcore4 (>=4:4.7.0), libqtgui4 (>=4:4.7.0) and libgif4(>= 4.1.4) which you should check beforehand.

Otherwise you may check in your distribution if boats is available:

Boats on Ubuntu.

Boats on Debian.

Boats on Fedora and Suse.

Mac

Disk image version 201204 for OS 10.5 on Intel.

Universal Bundle version 201004 for OS 10.4 and later.

Source

Source code for version 201204.

In order to compile Boat Scenario with your distribution of choice, you will need the development files for Qt4 and for libgif. On Debian and Ubuntu the package is libqt4-dev. On Redhat and Suse the package is qt4-devel.

For the adventurous you can try the cutting edge source repository