My gps is an Etrex Vista CX. It is a replacement one for the previous model that its rubber outer come
loose. TOPO GB was bought via a dvd. The maps have to be unlocked, that's why when you purchase
them, they come with an unlock code.
Edit:
It appears to be working now. By clicking into each region turns the selection into a different colour,
which then shows the name of the selection in the maps pane.
Thanks for all who offered advice.