Agent B-7

I use it to unlock the pneumatic traction lock on the locomotives that have it. Allows to apply the power while the rear of the train is still releasing the brakes, helps with hillstart etc (the brakes in the back will be eventually released and you already have some traction). Another thing is if you're switching and the brakes are in the T/G mode. If you intend to use only the local brake, you can keep it there and release the first time quickly with it. I know Americans use the independent brake bail to modulate the brake force or to use only dynamic brake on the loco itself, but it's definitely not intended use in Europe.

A mix of mistranslation (?) and weird ČD 163 controls. By "put the lever in the driving position" it means "release the brakes/charge the brake line to 5 bars". In most trains it means indeed putting into the running position, but on ČD 163, essentially the lap and the driving position are the same (the brakes are electronic), so you just need to hold it in release until the line is fully charged.