There’s a bit of a mix-up at Sencha lately with regards to their platform tools. I had to do some digging this morning to figure out that if you’re building a SenchaTouch 2.x application; you’ll need
This Package instead of Sencha SDK Tools
After downloading the sencha cmd stuff (which by default installs to your user folder) you’ll be able to run:
sencha generate app MyApp ./MyApp
Just like the shiny new guide says. The link on the guide page goes to the wrong place.