mai95

file now, you can change the address later, or use a family / friends address in the US.
they tend to not to worry much about the change in address, but you just need a valid address so they can send you any letter if they need to. so just make sure what ever address you put that you will be able to get mail there

An Update on this issue, The Embassy in Manila, issused a new visa, basically all the documents had to be presented again, so a whole new interview (ALL documents were neeed). They got their visa just in time with the delivery and flight they had less than 1 week to get married.
So in shorts it is possible,a new interivew, fees and all that need to be done again, and the 90 day requirement to get married started from the 1st time that K-1 entered in the US.
No questiones were asked why the I-1 went home,they did bring a new letter of intent from the US Citizen, along with ALL the same documents that were required at the 1st interivew. Medical was still valid so that did not need to be redone.

An Update on this issue, The Embassy in Manila, issused a new visa, basically all the documents had to be presented again, so a whole new interview (ALL documents were neeed). They got their visa just in time with the delivery and flight they had less than 1 week to get married.
So in shorts it is possible,a new interivew, fees and all that need to be done again, and the 90 day requirement to get married started from the 1st time that K-1 entered in the US.
No questiones were asked why the I-1 went home,they did bring a new letter of intent from the US Citizen, along with ALL the same documents that were required at the 1st interivew. Medical was still valid so that did not need to be redone.

1. above answers are correct
2. you can use the 100K as support for yourself, but best to put in joint account with her name also, yes you can use your own assets to support you, but it is difficult.
3. yes, usually she will just have to tell them that she will reestablish her domicile and or have an address you two will live at.
4. is the expiration the 4 months after USCIS approval? if so then it is probably still at the embassy sometimes up to an year. Best for her to write letter and cancel. just tell them you got married and will apply I-130, only she can cancel I would write letter, to both USCIS and embassy.(same letter) just so this will not be an issue later.