Copilot 7

Hi
I have copilot 7 installed on a PDA and when I try to input some even
numbered addresses it tells me the address does not exist. For instance:-
windsor terrace boston lincs has houses numbered 1 to 13 but copilot does
not recognise 2,4,6,8,10 or 12.
Also lacey gardens louth lincs has even numbers upto 52 but some of these
also don't exist on Copilot 7.
Can anybody try these on their copilot please as aAlk who supply copilot
says it is because GPS cannot pinpoint exact doors when navigating.
I told them I thought it was to do with their mapping software not the GPS
as tom tom and Navman both accept these addresses.
Regards
Pete