I would like just to extend my thanks to the great product that is the RFXrtrx433E. I've been looking for a simple product to interface to my Somfy RTS blinds and could originally only find horrible ugly hacks using original Telis remotes until I found the RFXrtrx433E.
The product was very simple to interface to and only took half an hour of playing around to get my blinds going up and down. The SDK documentation was a bit tricky to find from the website but Bert was very prompt to send it over.
One tip for anyone else doing RTS programming, you don't need to disconnect the power like it says in the manual - I followed the original Somfy instructions which suggested that it wasn't necessary. Though you may be taking a risk with this.
Here's a very simple video of my quick and nasty web control