Hi Jennaralissima,
5a - the 6 letter "Keaton film" goes around "slapstick originally" - definition is "chap keen to stay in" (think 'sport')
10a - the definition is "tasty little French thing" (a food) but if you read it 3,3,3 it could be someone telling their "Hubby (t0) pack your bags"
8d - 3 letter "fastener" + 4 letter "top" and single letter "new" - definition is "dark colour"
13d - 2 letter "that man" goes inside 2 letter "taxicab on vacation" and that all goes inside 6 letter slang term for "wife" - definition is "fail to grasp opportunity"