I fear my efforts are not going so swimmingly, being stuck on 3.
Assistance with a couple may, possibly, get me to the remainder.
10D Yodeller adds fine touch to piece (4, 7)
S?I? W???M?N
18A Losing tie, I didn't get that secured (6)
B?H?N?
Oddly I started this plea with 7 to get, but worked out 4 whilst typing (& retyping). I do think occasionally.......