The ROK Star machines are not backwards compatible. The new ROK Star Controllers cannot control the old vehicles and vice versa. The two systems can however, be set up side by side without interference.
The original Rokenbok system was controlled with radio waves. All the control pads were wired in to a central command unit. Rokenbok stopped manufacturing this system in 2006. The ROK Star system is now controlled with Infra Red technology and is completely wireless. The command deck and radio keys have all been eliminated. All building pieces as well as battery operated accessories are the same and 100% compatible across both systems.