A good place to start
The thread you reference is generally correct
For step 1
The zrts controller built in to smart things works well - so nothing to install in ide for this step
For step 2
I suggest the latest dth for the shades is created in the ide
https://github.com/imnotbob/SmartThings-1/blob/Develop/somfy_shades.groovy
Then follow the instructions for step 3
- Plug in the zWave RTSII Module into an outlet and follow the instructions to program your zWave Controller and blinds to your Smartthings controller (Manual121). For the channels (Virtual Node), in the ST app, you do Connect New Device, and then on the zWave RTS Controller, you add your virtual nodes. I had 5 virtual nodes, 4 blinds plus the "All Blinds: channel, They correspond to how my Telis remote is programmed.
The somfy support folks are good at helping setup of the zrts controller and virtual devices so if you still have trouble after following this give them a call