Care Bears/Headscratchers

So, in the second movie Dark Heart repents of his evil and becomes a real boy. Good for him. However, he has no parents, no birth certificate or any other kind of records, and no experience whatsoever with the world outside his pocket dimension. So, he's basically a homeless orphan, with nowhere to go.
- But that's not so bad; the Bears took care of a case like that in the first movie.
- Undead Tax Exemption time!
- Kind of moot considering the kids seem to be living their lives in a summer camp with no adults. Maybe they're all orphans.
What is Dark Heart in the first place and why does such a seemingly powerful entity care so much about the Care Bears and this one stupid summer camp??
Also in the 2nd movie: where do the Care Bears come from? They are shown sailing a boat in the middle of the sea and then being taken to Care-a-Lot by some giant Star-God. Are they from Earth? Another Planet? Another Dimension? Why are all of them babies? Did Dark Heart kill all the adults but two?
- In the UK comics they were normal animals given their new forms by the Great Star, but its not officially a cannon-set-point.
- I assume they were from another dimension.
In the DIC TV series and the first two films, Billie Mae Richards voiced Tenderheart Bear and Jim Henshaw voiced Bright Heart Raccoon. However, in the Nelvana TV series, their roles switched. What reason was there for that?
- Maybe they were jealous of each other?
  - Doubtful. There has to be some type of reason.
- Maybe they just couldn't remember who played whom. It's not like the Care Bears got very unique characters, after all.