Jogamel, if you've now got the correct phrase, jot down the letters in words 1, 2,4 and 7. Cross off the letters that you've used in the grey bits in 1 D, 7 A and also the letters in the other grey squares. You'll be left with seven letters - those plus one more (a consonant, as suggested earlier) can be anagrammed to give a final thematic word.