yes, I saw that. but they landed Wellington, where as 'my' lot, are definitely in Picton from 1858. Hence my thinking that the Downes mentioned as 'for Nelson' in the newspaper might be them.
What I have not done, is checked to see if Walter is connected. (This is research for a friend and I have got a bit side-tracked whilst waiting for some certificates for another branch of his family... as you do!

The family I am interested in are Thomas William DOWNES and his wife Sarah Rebecca, with a lot of children. The eldest born 1837, and the youngest 1850. (This is TWD no 1. he had a son, and a grandson both of the same name, who feature heavily in the Alexander Turnbull, DigitalNZ etc)
This is Thomas's second marriage, he is elderly, (b abt 1786) don't know what he was thinking to risk the voyage) and it is possible Walter is a child of his first marriage, Which I have yet to find, although a tree has a suggestion I have yet to check. (they have Thomas William dying in London in 1856, instead of Picton in 1866 so one of us is wrong).
added - I have just noticed the number 9 in brackets (9) on the next line after the Downes and family. And that is how many there should be 2 parents, 7 children.
added further The Turnbulls on that vessel were Walter and Adelaide. Can't help wondering if there is a mixup going on.