In regards to the minor changes, they are always undesirable, but each were concessions that we felt necessary to allow deterministic playback and uphold the quality of the movie.
The issue with camera shake causing some entities to randomly load at different times could disrupt enemy cycles. This can be very problematic with attacks requiring frame perfect timing or tight cycle-based grouping of enemies to allow multiple to be destroyed at once. Camera shake RNG is unaffected by gameplay, so we chose to remove it for the sake of determinism rather than sacrifice time attempting to correct for its inconsistency.
The change to time in the game loop was necessary to ensure both that load times were consistent (which would otherwise vary randomly and by machine) and solve the problematic issue that when you gain character control in a level could randomly vary by a frame. The variance in gaining control would mean having to create scripts that would work for both starting frames, which would sacrifice at minimum a frame in every level and would overall reduce the quality of the gameplay.
To verify the faithfulness of the modified game, we can compare the play between the two using composed individual level replays. These replays (which are input-identical to the level portions of the full-game script) can be seen to sync on the unmodified game 90+% of the time. Although we cannot verify the gameplay in the overworld outside the levels, neither of these issues are a problem there since there are no meaningful entities for them to affect.