Flipping the bird is unbound at default you can find it in your controller assignments under "taunt" I bound mine to f4.

Bottle in your hand, go first person. Might have to fiddle a bit but the base of the faucets definitely works if you aim on it and use the scroll menu to Fill bottle. Wells that are boarded of does not work. Any ponds you find are also useable but might be infected. Faucets have all been clean water for me so far.

Getting Saline from a friendly player returns the colors, I'm not sure if you can use it on yourself. About the gaining of blood by beeing hydrated and full on food I too am skeptical about whether or not that actually works (That is however the way it is supposed to work).

Haha, great story!

Yup, same problem