1. Skirt or skirts for boy? I don't know. Bypass.
Presumably skirt is the definition and the clue is By (abbreviation of 'boy') and then pass (I don't know) but where does the word 'skirts' in the clue fit in?
2. Absolutely unique as this grid entry. From top to bottom.
Absolutely is the definition and the answer runs from the top of the grid to the bottom so that's the wordplay but why 'unique'?
3. Bill has to cut through weed. Baccy
4. No challenge? Gulp. Pushover.
Sorry to be so pedantic but these are bugging me!