CMM for me - and if you must get the M out of the wall, just ensure that the straight lines going 'through 11 cells' leave enough room at the edges to contain the letters without overwriting them.
Am just tidying up... does it matter HOW the fourth thematic item is entered? I've just noticed that two versions are possible (the middle letter in the original answer could go first or last in the entry).
I've done everything apart from the eight straight lines through 11 cells. Am I looking for the name of the house in the novel by the second named person? If so, there are only two Gs. I've been staring at this for some time!