Gitto:
1d — the definition is four words and the omitted letter is a consonant
20a — lose something from a word defined by profits (I wasn’t aware of this definition but it’s def #6 in my copy of chambers)
18a — two 2-letter abbreviations with a vowel omitted
35d — take a letter away from an obscure word for ‘ball’ (which is archaic as a noun but not as a verb, apparently)
36a — three word definition, the synonym for shops is the obvious one
31d — this is the only one I haven’t parsed either!