Comment 1 for bug 1007539

Hello and thank you for this bug report!

That should be fixed in BZR repo (I guess they have changed something in X server...) ;)
  https://bazaar.launchpad.net/~cairo-dock-team/cairo-dock-core/cairo-dock/revision/1091/src/gldit/eggaccelerators.c

Note that as workaround you can edit the shorcuts manually and replace <Primary> by <Control>