Across:
   7. Country taking advantage of an opening after leader dumped (9)
   8. Odyssey perhaps a partial depiction? (4)
  10. Our duty is to protect language (4)
  11. Sort of degrees with tragic need to change (10)
  12. Currency being up involved in coat being returned (6)
  14. Taking to court over right to pursue popular covering (8)
  16. Bad habit: losing one's money (4)
  18,29,22dn. Dodgy clinician is as far in as when 17's 16, 23 19 and 9's 12 27 (7 and 20 also affected) in 1997 (5 9 6)
  19. Pose problem: not much money (4)
  20. I may sail off for another country (8)
  21. With company, company like drinks (6)
  23. Greek character with border tree like in Manila? (10)
  26. Dodgy tips from industry fuelled fatal year (4)
  28. Eastern home garden (4)
  29. see 18
Down:
   1. You may end up exploited by such tricky ruse (4)
   2. In Spain, Cubists were supposed demons (6)
   3. Vipers chase a "lend" arrangement (10)
   4. Behold: article which may attract interest! (4)
   5. Some eye tiger as legendary 18 beast (4)
   6. Parroted foolish show of emotion (8)
   9. I do insane stuff in the country (9)
  13. You auction every last one, knocked down without reserve (9)
  14. Island alibi Zappa provided (5)
  15. Ray does less harm when these are used, but runs scenes badly (10)
  17. Country had Latin letters (8)
  22. see 18 across
  24. "Dragon" turned up very loud (4)
  25. Bars popular Poles (4)
  27. Hide in the hills (4)