Of course I would like to help you with this situation.
To answer your question : I am using Galera/HAProxy for both Kloxo-Mr Control Panel and to install clients. Just finished some sort of plugin to do this. But let me explain first how I set it up the first time.
Very simple .. I just copied the existing database of Kloxo-Mr to a Galera Cluster and with some little changes Kloxo-Mr was ready to use the Galera Cluster instead of the local database server.
I am a little busy now expanding a few things but I will provide a detailed installation manual here at my own Social Blog :
http://Blog.WebLogin.xyz/ (I will put a copy on the forum here later on when I finished my own situation.)