Dean,
I did not include this title in the list of sources providing a Portuguese perspective as it deals with the actual transfer (as opposed to the events and considerations leading up to it).
I did though refer to it in my research and referenced it in my MA, and you might find it useful yourself (a couple of pp infuriatingly missing on google).
As issues that were not directly relevant to the situation in Portugal were not of principal importance I did not include them, but Sir S Smith's schemes and activities, whilst in Brazil, and his subsequent recall, are covered.
Neill Macaulay, Dom Pedro: The Struggle for Liberty in Brazil and Portugal, 1798-1834, (Durham, NC: Duke University Press, 1986)
https://books.google.co.uk/books?id=__0KrEZGkmUC&printsec=frontcover&dq=neill+macaulay+dom+pedro&hl=en&sa=X&redir_esc=y#v=onepage&q=neill%20macaulay%20dom%20pedro&f=false
Best wishes
A