13 down Caine's key position in British film making THE B?N???N; 17 down An Irish Sea island once had Charlie and a prince as men living in cells ?O?A???L; 23 down Rhymester engaged in Japanese poetry? Just the reverse R???A; 24 down A demon and I - we fight ???I; 25 across Ponderosa's one tree in part - not Bay R???? and 26 across Poem I'd heard on champagne - very old and very dry ????I?IED - have been stuck on these last interconnecting clues for ages - could really do with some help!