4 down - wavering, tempermental, volatile (8)
7 down - family planning (13)
15 down - solitary person (4,4)
19 down - depressing, not bright (6)
20 down - Complain, whine (6)...
1 - Imaginatively amusing (5) 2 - Variety of surveillance (4 and 7) 3 - Airtight receptacle for processed foods (3 and 3- tin can perhaps) 4 - Cog shift handle (4 and 5) Thanks