What should I be aware of when using an adaptive cruise control system?

You answered correctly. Even when using adaptive cruise control, you must stay attentive at all times because the system is only a driver assistance feature, not a replacement for your attention. The system can be impaired by heavy rain or snow as sensors may not function properly in these conditions, making it less reliable. Additionally, you can always override the system by pressing the accelerator or brake pedal. Understanding these points helps ensure safe and correct use of adaptive cruise control under German traffic rules.