Renee Montoya is portrayed as a uniformed police officer in this story which is set after "The Adventures of Batman & Robin" (1994) where she was promoted to plainclothes detective. Both SubZero and the series are part of the same continuity that began with the 1992 "Batman" animated series.
When Bruce uses the computer in the hospital to search the blood donors, in a wide-shot he clicks "send email" with the mouse. In the next close-up, the cursor is back to the original point, and he then moves the mouse, but now to click "search organ donors".
When Bruce uses the computer in the hospital to search the blood donors, when he opens the organ donor form, the form on the screen already has some of Barbara's details filled in; obviously a glitch, as in the next shot the whole form is empty, and Bruce then goes to type her name in the form and searches for the information.
At the hospital Belson agrees to use a live donor for Nora Fries and searches for blood donors. The computer screen already has 9 results for gender, height, weight and blood type AB negative. In the next close up, the blood type is blank, he types AB negative and finds 18 results.
Near the end of the film, when Batman attempts to save Mr. Freeze with a grapple gun, a piece of debris from the oil rig hits Batman's shoulder, causing him to drop Mr. Freeze. He reaches out with his right hand, which is no longer holding the gun. After Mr. Freeze falls, the gun is back in his right hand, and he retracts the cord.
When an explosion occurs bad enough to cause a huge part of the structure to fall, and Belson shoves Freeze away from him and runs, you can see it looks like Freeze gets completely buried. In the next shot, it shows only his lower half is buried.
Robin shoots Barbara a line at the top of the oil tank, and the next time we see her, she has a pipe in her hands, which she uses to slide down the line, before it snaps and she falls to the ground. Where did the perfect pipe come from?
When Barbara tries to escape for the second time during the climax, Belson gets a revolver out from a drawer and shoots at her (which leads to Batman and Robin rescuing her and the oil derrick going up in flames). If Belson had a gun the whole time, why didn't he or Mr. Freeze just kill Barbara when they brought her to the derrick and then do the organ transplant instead of just keeping her captive?