Across:
   7. 6 fellow to lie about offensive (8)
   9. No deep changes went in at the start (6)
  10. Temporarily live at 100A (4)
  11. Was heroic leader in George not backward as president? (10)
  12. Sources of great unhappiness include popular form of TV programme (10)
  14. Awesome rotation of core spices (4)
  15. Second man getting first lady mounted like Mary is (7)
  17. Student exercising special powers exchanged second and third letters expressing ideal (7)
  20. Redding, one of the musicians (essentially egotists) (4)
  22. Crazy southern ones completely exclude north in repository (10)
  24. Carlo sang "El Estado", using American place's Spanish name (3 7)
  26. Boy works and dances (4)
  27. Keep a god at home, for public building lacking god (6)
  28. These can help her with inspiration when doing her nails (8)
Down:
   1. Rudolph inspires group who may have distinctive noses suggestive of the bottle (8)
   2. Watch TV, i.e. what's offered! (4)
   3. Sweet outcome of careless summer outing? (7)
   4. It's arranged with art, for cinema to serve? (5 5)
   5. Tandem bicycle a guest showed off (6)
   6. Luciano medley brought back by Lucifer? (8)
   8. State heart of existential claim in triplicate (5)
  13. Smashed single taxi which may be seen on roundabout (4 6)
  16. Country's anti-loan arrangement (8)
  18. Sport where I flail boot around, repeatedly missing one! (8)
  19. see 23
  21. Maybe fall for Spice? (6)
  23,19. U.S. 2: blip, or aberration, when the 8 1 did the 11 3s in 24 for the only 17 21 in the 16 18 5! (5 4 3)
  25. London district school upset with removal of roman numerals (4)