Executive Meddling: If this is to be believed, Universal executives were horrified at Woo's original cut of the film (as was star Jean-Claude Van Damme, who complained that there was "not enough close-ups") and ordered major edits to the film in order to tone down the violence and make it to where it was presentable (in their minds) to audiences. To prevent Woo from interfering, he was locked out of the editing room during post-production. The same thing would happen to Woo again with Mission: Impossible II, in which star Tom Cruise took issue with Woo's cut of said movie.
Missing Trailer Scene: The theatrical trailer shows Van Cleef saying "Look at it this way. You gonna get to meet Elvis" while kneeling over dead body of Roper after his men killed him on street. This short dialogue scene is not in any known version of the movie.
Production Posse: Several of executive producer Sam Raimi's crew carried over to this film, including screenwriter Chuck Pfarrer, editor Bob Murawski, and stunt coordinator Billy Burton.
Throw It In!: During the final battle, Lance Henriksen's coat accidentally caught fire. He never broke character and continued the scene while he pulled off the coat and threw it away. This remained in the final cut.
Uncredited Role: Executive producer Sam Raimi did rewrites on the script, and also directed the film's opening sequence.
Wag the Director: Jean-Claude Van Damme would often second guess John Woo and in post-production, he went with his own editor to make his own edit of the film. Van Damme's version excises whole characters to insert more scenes and close-ups of his character Chance. When asked about this edit, Van Damme replied that "People pay their money to see me, not to see Lance Henriksen".
Sam Raimi was hired by Universal essentially to act as John Woo's minder, monitoring the production to make sure he was working on schedule, with the implicit understanding that he would step in to replace him if Woo fell too far behind schedule or was otherwise fired. Thankfully that never happened, and Raimi wound up becoming Woo's fiercest defender, even getting into a shouting match with execs to defend his autonomy
Hard Target 2:
Refitted for Sequel: The horse chase in Hard Target was originally supposed to be a boat chase, which was cut due to budget problems. In Hard Target 2, one of the key action setpieces is indeed a boat chase.
Sequel Gap: Was released 23 years after the first movie.