I just tested the code here.on a Samsung Tab II . The Speech Recognizer works BOTH using WIFI and also with turning off the WIFI (internally). The tablet uses Android 4.2.2
Are you using a phone ? What operating system. How are you connected to the Internet .... WIFI or a G3 network or something else?
I do not get the error messages you get. What do your blocks look like? The code is very simple, but perhaps you made a coding mistake? Another possibility is that your device does not have the internal SR software from Google. You get a message saying you can not reach Google ...so just try again. Can you access Web pages using your browser?
Regards,
Steve