I found what appear to be a few glitches in the Bandai Burgertime game: the first bug I found can be done by repeatedly pressing the down button while standing above the bottom bun on the first floor; this causes both the top and bottom burger buns to appear, completely eliminating the need to enter the top floor.
The second bug occurs after beating 5 rounds, at which point the enemies and ladder barriers stop moving completely and don't respawn when eliminated.
This effectively allows you to play the game indefinitely, which if you get beyond 19K points causes the score counter to break, though this appears to be a limit of the original unit being unable to display past that number correctly.