I’ve just started playing around with fvwm-crystal on Ubuntu, and I’ve run into an issue that others may have, too. Out of the box, I didn’t have any application menus showing up. It turns out that fvwm-crystal is sensitive to what version of python you are running on your system. Once I changed the symbolic link /usr/bin/python to point to /usr/bin/python2.5 rather than /usr/bin/python2.6, all of the scripts to generate the application menu worked. This should be stated somewhere in the documentation. If you run into this issue, you can simply delete the old symlink with
sudo rm /usr/bin/python
and create a new symlink with
sudo ln -s /usr/bin/python2.5 /usr/bin/python
Hopefully this helps other people in the same boat.