Wow - finished and sealed up - this one took me nearly a week to struggle out (No Cheats, No Lookups, on principle, remember) - i'm still not sure why some of the answers are what they are - the Dutch, English and Spanish lobbed bottles one still has me completely foxed, although I think there's only one workable solution.
This setter has an imagination that roams far and wide, and some of his/her weirder allusions are only marginally connected: 'Do out' - but where's the potter? Anyway, enjoyed the memories of M. Swann, The bells! The bells!, the Pink Panther, 'baked under rockweed and poppin' from their shells....', Hey ho! Hey ho!! etc etc etc. now to see if anyone else thought it was hard, or if it's just me.
Incidentally, did last week's by Tuesday, in spite of spending the weekend in trench warfare with the taxman - right up to the wire........