In self-learning mode, tailor the neural network according to your preferences by modifying the parameters within the input columns and pressing experiment
On manual mode, press the arrow keys to navigate through the traffic
Press the "change" button to generate a fresh backdrop with altered settings
And yes, the NPCs (Non Playable Cars) have unwavering focus and continue on their straight trajectories. Also, they could move over another ,underneath or within, depending on how you decide to see it :)