From what i heard she got the idea from the Dutchess Of York who started a similar project in the 80s and Rowling made her own version from that idea, only resemblence i see from troll is the name Harry Potter which is a common name i suppose.
"I used to be indecisive, but now im not too sure."
Please... The Dutchess of York not withstanding.
Granted there is some controversy stirring, and rightly so:
The movie has a young boy as it's hero and his name IS Harry Potter, AND there are all of the simularities:
-- Again, the Harry Potter in TROLL does not have anything as contrived as a lightning bolt scar, he is hero of the piece and is about the same age, the same coloring, and dresses similarly... the costume (plaid Flannel shirt worn over a dark blue T-shirt, and dark slacks) Harry Potter wears in the finale of the movie TROLL, is very similar to the wardrobe as depicted in the sketches from the books, as well as the first time that we are introduced to him in the Warner franchise movies...
--And though not quite a wizard yet, he does learn about magic from a witch (remarkably similar to Prof Mc Gonigal, dresses the same, --same victorian gown, similar neck broach on her high collar, hair worn up in a bun) though not at Hogwarts admittedly, she does in fact teach him the ways of magic just the same) and she gives him a magical staff to do battle with...
--And though the young hero called Harry Potter in Troll dosen't have a portion of the dark wizard within him, --he does have to confront the evil wizard that has come back, transformed into a hideous troll (Turok), not unlike another wizard that came back transformed into an evil snake-man (Voldemort) both vowing revenge and campaigning to take over the world...
--And he does have to confront a giant troll to save a little girl (Wendy Anne) in Troll, not unlike another Harry Potter who has to fight a giant troll in the Sorcerors Stone to save a little girl (Hermine)...
--And as there is no Hogwarts there is no Ron, Griffendor etc.. My guess is that J K Rowling must've "borrowed" the boarding school concepts from the WORST WITCH TV series, that was playing in the UK on the telly about the time that she created her stories. The prototypes for many of her featured characters are in the series
The otiginal movie TROLL, had the story AND the character first. Witches, fantasy worlds, a heroic kid named Harry Potter, and magic...
There won't be too much confusion either. It will be pretty obvious that a magical boy named Harry Potter has been around since 1986, and this a remake of the original!