I've done a few T/Tom go camera installs, it should be the same

Once you have the files in the Great Britain directory:

Go to Change preferences;
Maintain POI
(this brings up list of POI);

Select each camera type ( gatso, temp, spec, redlight,etc) ONE AT A TIME.
Enable POI
Tick WARN WHEN NEAR, (you can set distance)
Then choose alert tone. (cow or cukoo is best, you really notice them)

Repeat from camera type for EACH type One at a time.

Make sure Enable POI in ticked on main screen after install.