Hi Grunger,
2a - definitely a sneaky clue as it looks for all the world like it's Delia Smith's sauceboat - but it isn't.... - You need to alter a letter in the first word to - 4 letters for "floated" + 2 letter abbr."past" around the three letter "snake" - It's a type of vessel you might need in the everglades in the US.