Then they had to get a code for the level which was done directly from within the game.
The game originally had a level editor similar to Lunar Magic where users can create levels. Now here's a fun fact: I've never actually beaten the main game of Flash 2 back then I just mainly focused on the Level Portal option the game had where you can play custom-made levels from users on Pouetpu. I remember playing this game on Pouetpu-Games when I was much, much younger along with Flash 1.