At this point you should have a working CM11, and a device in your home installation, for example a dimmer/switch module such as LM12. It’s time to install in your Linux the software to manage your devices. It’s called heyu.
You can obtain it here, even if it’s open source, still can’t be find in all the linux distributions because it used to have a particular license that make it not totally opensource.
Fortunately, the license changed on 08/2011 to the compliant GPLv3 adn in the future it might appear to your favourite linux distro.
In any case it worths the hassle of having to go to the site and donwload the software, because it makes controlling your X10 much easier. To install you just have to download the tgz file.