I just recently played the remakes of RE 1 thru 3 (waiting for the 4 remake) along with 7 and 8. The games got me heavy into the world of Resident Evil. The director did a good job portraying the stories of both RE 1 and 2 together in one movie. Sure there were differences, some I didn't care for, but it was very entertaining for a fan of the games. I imagine some leaving bad reviews were either 1.) knew little of RE and went in to just watch a horror movie or 2.) are your typical overly critical gamer types who refuse to let people enjoy things. Look how successful and loved the MCU is and those movies stray away from the original Marvel comic books. This could be a slightly new look into the RE universe and I'm here for this new franchise.
Spoilers:
Wesker was an evil behind the madness in the games where his character in the movie seemed to be more dumped into the madness without his knowledge. Oh well. The actors didn't physically resemble the game characters well, no biggie. I love seeing the beginning of the creation of Mr. X and look forward to his presence in the next movie.