Follow what Loly's said above. In explanation, you cannot use the British English Voice Command without both an appropriate english TTS *.vpm voice file in Voice folder and en_GB.srd in ASR folder and the full EU map. You may also need to set the unit to UK locale.
See here for more info: [Only registered and activated users can see links. ].
Yes, it won't work without it as said. If that's all you need it's attached here:Do I need the "en_GB.srd" file? - Where do I get it from? Any advice on where I begin please.