My gastric juices are flowing Roof:-)
4a definition is "sign of support" (act of goodwill) - 4 letter word for "rowing crew" (half the usual number beloved by setters) around front of A + V(essel).
12a definition - "they don't appreciate" - empty A(r)T inside/framed by "French painter"
6d definition - "Ring fan" - anagram of O(ld) Pro Agree
7d My COD - definition - "Elizabeth I say" - 4 letter synonym for "study" around usual abbr. for "Edward" and "Henry".