I've finished, but not confident about two.
7a Interfere with dog without a tail (5)
?N?O?
I've gone for SNOOP (the dog being SNOOPY), but it doesn't really mean "interfere", does it?
20a Embedded level inside trendy top (6)
I?L?I?
I've gone for INLAID. This time the def. is OK, but I don't see all the wordplay ("in" for "trendy" and "L" for "level" perhaps, but that leaves "aid")