It'd be useful to have (optional) hints that can appear when you use a control and it doesn't do anything. Most often that would be applying power and the train not going. For example: You only reset the power controller to "min" rather than "off" then used the brake. Power controller must be reset to "off" before it responds. (For most of the German locos) You haven't turned the "brake" key (for the German cab car) The emergency brake valve plunger is out so brakes cannot be released (for the Class 66) PZB has gone off and you haven't randomly fiddled with the reverser, brakes and PZB keys until you find the combination that somehow resets it (Germany) You changed gear too quickly and so the train isn't in gear (BR 101, UK) You've tried to open the doors but the reverser isn't on so I've ignored it (MSB) etc. Obviously getting a comprehensive list of everything would probably be impossible, but providing the common stuff that often comes up should be doable. A lot of this isn't in the manual (which is probably fair enough - it'd be impractical to document every interdepencency and make heavy reading) so this kind of information would be useful to help people get going.