Google changed the terms of use of how sms works on Android over a year ago. It means parts of the No Texting While Driving tutorial are no longer correct
What changed with respect to Texting now works is described here> Texting
These changes to the way thingss work means that developeers have to make adjustments to the No Texting While Driving tutorial. To get the tutorial to work almost properly, compile the app using Companion 2.60u to expose and use the SendMessageDirect block. Use the SendMessageDirect instead of the SendMessage block. You should test this on a device with the apk. Also be aware, comments with respect to GoogleVoice may no longer apply either.
You need to set ReceivingEnabled to 2 or 3. Be careful with 3 (see the notes in the Texting documentation).