Auto sourcing, which refers to your input connection. It will scan for what type of input you are connect to and turned on. I would not recommend using European standard with the possibility of frying your circuits.
You need the VP3D1 to watch 3d, not hd. BTW the VP3D1 is discontinued because they are coming out with a new model. The only way around a 3d processor (like the VP3D1) is to run the 3d through your computer if it can output frame sequential.
No, unless you hang the projector to a ceiling mount. This requires the projector to be attached upside down. The projector has setting to flip Picture, but you'll still have to place where you're not in front of the light beam. if you have the room space. This projector has rear projection, but require the purchase of a rear projection screen. This would be the best way to achieve what you're trying to do.