1. they can act as if they were that person
2. not sure - don't think there is any extra EPA's are being phased out from about 5 years ago, but anyone that has one can still use it
3. no conditions at all as far as i know except the person giving it has to want to and has to have mental capacity. I am a perfectly healthy person, but ii could give my husband POA if i wanted
4. again, i'm only answering on behaf ofLPA's (which came in when epa's were discontinued) but i'm presuming if the person themselves could do it, then any poa could also do it
5. poas cease to be valid on the death of the person. If the person dosen't have mental capacity, they can't make a will anyway. I am unclear what you are asking - is the person dead?
6. when i did my LPA i could nominate people to be informed if it was activated, but i didn't HAVE to nominate anyone