Hi Lumen,
27a - Single letter "caught" + 4 letter "catch" minus its first letter/"topped" - definition is "onion net per records" -
15a - If you look up the 2 options for the last letter in Chambers you'll see one of them is a "drug to America"
35d - 4 letter "fast" minus "top of tickly" + single letter "zip" - definition is "cloth"
27a and 35d contain extra word