The Japanese version has a few graphical differences compared to the American version:
The current score isn't visible on the end-stage results screens (points are still being awarded though).
The cross sprite before collecting it is more similar to a Christian cross and is more akin to the sprite used in Rondo of Blood.
The tombstones used by the Stage 4' Boss during its second phase have a Christian cross (as opposed to a skull in the American Version)
When Richter gets hit, he flashes red (as opposed to white in the American version).
When Richter dies, he dissipates in a red particle effect (as opposed to in a white flash in the American version).
When Death dies, his scythe decapitates him on J.
Death's death animation is around 25 frames longer on J. This makes the American version faster for Best Ending, and is the only speed difference between J and US.
The Japanese version lacks the unskippable copyright screen on boot up, giving it a faster reset time.
The PAL version runs at 50Hz and is thus slower.
Timing
Time starts on first frame of control, and ends upon grabbing the final orb.
You can use a -7.00 offset from the title screen.
Categories
Dracula X categories are split by endings:
Any% gets the Bad Ending (Falls into stage 4', then goes to stage 5)
Good Ending saves Maria but not Annet (Goes to stage 4, then fights the minotaur and proceeds to stage 5)
Best Ending saves both Maria and Annet (Goes to stage 4, then takes the door and proceeds to stage 5')
Any% Whip Only forbids the use of subweapons and is restricted to the whip.