There was no Compton Place in St Pancras in 1861. There was a Compton Street, but this seems to list a tenement block which stands on Harrison Street, with exits on Compton Street.
I use The Genealogist for address searches, although some people have said that they have success on Ancestry on some censuses by putting in the address into the keyword search. I haven't tried this myself, because I prefer the search on The Genealogist (I subscribe to both).