Clipsal is not compatible, and afaik, does not have free open programming interfaces available.
If you already found out that less expensive stuff has its draw backs, and it might make sense to spend a bit more, why not look into KNX? It is supported by LinuxMCE, world-wide available, and completely manufacturer independent.
One thing you will need to do, is rewire, because otherwise the devices are way too expensive.
I had a good chat to a local supplier of KNX units. I understand what you meant by rewire now. And KNX seems to be the better route to follow. Just one more newbie question...... The supplier asked if I wanted the "ip-gateway" to interface with my LMCE or a serial interface controller?
Which one would you reccommend?
They also have a weatherstation that would be nice to include in my setup...
I'll have to save up for it though....