Comment 5 for bug 330193

After $ sudo apt-get install btnx
I also got these messages at the end of the installation output.

Setting up btnx (0.4.11-3ubuntu2) ...
Starting btnx : Button Extension - mouse button rerouter daemon
 btnx: uinput modprobed successfully.
 btnx: Could not read the config manager file: No such file or directory
Segmentation fault (core dumped)
btnx failed to start (error code 139) - try btnx-config