That’s normal when there’s nowhere to turn the locomotive around, especially on a cog railway where loops and switches are more complex and expensive. On a steam cog railway, you want the locomotive at the rear so that if a coupler fails, the locomotive is in the way and can bring the train to a safe stop. It wasn’t common for railway wagons and coaches to have their own brakes back when these were built, besides a manually operated handbrake.

I don’t know about American ones (but I’d assume similar), but in British ones, they were often absolutely full of asbestos - the boiler, cylinder and all the insulation on everything, but also other stuff like insulating the walls in carriages, and basically anything else which needed padding, insulating etc.

Basically it’s everywhere that you’d want to use a magical fireproof super-insulating wonder material with no downsides at all *cough* *cough*

I think any ones which are restored and running in heritage railways have had it replaced, but it’s definitely still hanging around in some of the ones in museums etc.

Couldn’t tell you, but the boiler is clearly insulated pretty well.