Hennig began her career at Atari Games, one of the pioneers of the video game industry. Her initial roles likely involved art and animation. Her first role on a game was as an artist on the Atari Lynx game 'Electro Cop'.

Hennig moved to the 3DO Company, a platform known for its CD-ROM-based games. Here, she gained experience in level design and game design roles. Some of her work included the game 'Armageddon: The Alien Apocalypse'.

Hennig worked on Michael Jordan: Chaos in the Windy City, a side-scrolling platform game released for the Super Nintendo Entertainment System (SNES). She was an artist and animator.