New Zealand national ...

Hello once again !
I have a cl aged 69 who is from New Zealand, does not have dual nationality, and she came to uk 02/10/11.
My understanding of her right to claim P.C and C.T.B are as follows.
As a commonwealth citizen she has right of abode which means she can claim above benefits.
However, she only has a New Zealand passport and page 38 of th Benefis for migrants handbook appears to indicate that the only way my cl can prove she has a right of abode is if she obtains a UK passport, and she only has a New Zealand one ?
As ever, any thoughts greaty appreciated ... and nearly the weekend ...
... HOORAH !!!

She can have the right of abode if:

her mother or father (if married) had British nationality otherwise than by descent; or
she was before 1 January 1983 married to a British citizen (it would then have been a Citizen of the United Kingdom and Colonies, generally by birth in the UK).

Hmmmmmm ... plenty of food for thought and to read, and thank you for the replies.