Northstar - recap:

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Across
  1. 4. Nonsence, gibberish
  2. 6. Beyond or above the range of normal or physical human experience
  3. 8. An irresistible urge to behave in a certain way
  4. 11. An excessively cheerful or optimistic person
  5. 12. A lack of success in doing or achieving something, especially in relation to a particular activity
  6. 13. Not affected by alcohol; not drunk
  7. 15. An act of becoming progressively worse
  8. 17. Satisfaction or happiness as a result of fully developing one's abilities or character
  9. 18. Adj - E.g. a characteristic or disease, determined by genetic factors and therefore able to be passed on from parents to their offspring or descendants
  10. 19. The period a drug addict goes through following abrupt termination in the use of narcotics, usually characterized by physical and mental symptoms
Down
  1. 1. Put in a very difficult situation, vulnerable
  2. 2. Strong attachment (to) or affection (for a cause, person, etc.) marked by dedicated loyalty
  3. 3. An extremely wicked or cruel act, typically one involving physical violence or injury
  4. 5. Adj. - giving rise or likely to give rise to public disagreement
  5. 7. The most important part (or something that you can hit with your car :-)
  6. 9. Present or deal with (something) in a vague or inadequate way, especially so as to conceal the truth or mislead
  7. 10. An arrangement to do something or go somewhere at a fixed time
  8. 11. The state or condition of being preoccupied or engrossed with something
  9. 14. Not revealing one's thoughts or feelings readily
  10. 16. Refuge (mental hospital)