Oh. My bad.
At building of a package I have forgotten to specify dependence 'coreutils-gnu'.
I'll fix it in next release.

But why you have no permissions write to the vibration device... I don't know.

Please:

1) show me a file:
cat /etc/event.d/out-call-vibro
2) Try to reinstall a package:
(on root)
apt-get remove out-call-vibro
apt-get purge out-call-vibro
apt-get install out-call-vibro

And when do not restart a phone! Try to call.

PS: yes, current version is 0.5