(at around 7 mins) During one of the early observation room scenes, Colonel Reynolds right (on screen left) epaulet clearly bears the rank of colonel, while his left epaulet (on screen right) bears the rank of lieutenant colonel. In the previous scene as well as those immediately following, both epaulets bear the rank of lieutenant colonel.
During the entire attack sequence the test subject zombie is shown to have 2 individual leather cuffs on his ankles but is able to move freely. However after he is shot the second time and and the 2 lab techs are shown putting him back on the gurney there's a new larger strap binding his ankles together and the tech at the foot end couldn't have placed it there since he goes directly from holding the weapon to lifting the zombie's legs
The military rank insignia on Colonel Reynolds jacket keeps disappearing/reappearing throughout the movie. Especially while he is in the control booth during the experiment at the beginning of the movie.
When Julie drags the corpse of Santos through the door by its almost severed head,the direction of the head changes back and forth. One moment she holds the head by the neck, the next moment she holds it by the chin.
When Curt and Julie run out to the van and are joined by the shop keeper, the police skid to a halt and get out of their car. The front driver's marker light is out. After firing at the fleeing van, the light is on.
When they are first testing the Trioxin gas, one of the signs that it's working is that the corpse attains a heartbeat. Yet, in the first movie, the two characters who were first exposed to the gas *lost* their heartbeats, yet were still mobile. Therefore, heart rate should not be used as an indicator of Trioxin's effectiveness.
This is just after Curt reanimates Julie with the 2-4-5-trioxin about 30 minutes in. When Curt is trying to seal the airlock to escape a zombie, he clearly turns the airlock seal in the "unlock" direction instead of "lock".