It depends on the canon being contradicted. If they suddenly say "lol JK Yoda didn't die" I'll be annoyed. If they say that there was no truce at Bakura, I'll be fine.
Other than that, Kyle Katarn being there is a must, Rosh Penin is optional, Jaden Korr is optional (mostly because they were relatively minor video game only characters), and the Thrawn Trilogy must be kept intact.
Other than that....Chewie dies? Jacen goes all evil pants? Some fat evil wound-in-the-force/shapeless blob tries to eat Han and Leia's son, conveniently enough named Anakin? It can all be disregarded.
I would enjoy seeing the events of The Courtship of Princess Leia in film, if only because it would 'complete' that arc started in A New Hope
Proud of the Six One Seven.
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