Miss Davidson, I agree on some of your points but not on others.
1. The children should have been allowed to leave unharmed, I agree with that.
2. I also agree that they should have had the chance to take their personal property with them, along with the money that would be theirs. This poses a very tough question because I think it would have been very hard to determine what assets belonged to the IF and what belonged to the State, that is, to Russia. In another part of this forum, someone said that Nicholas II had filled out a census forum saying that Russia was his or something like that (perhaps someone could find the right quote for me - thanks).
3. At the time I think an international court was out of question. I don't think there was an international legal framework to make this trial happen. The League of Nations wasn't even in the making, let alone the UN or other international tribunals. Since the vast majority of the activities of the Emperor took place inside Russia, he might have well insisted to be judged under Russian laws, which in turn, gave him the chance to do what he did, as he was the Autocrat and had the last word. He would have predated Richard Nixon in saying "if the Tsar does it, it's not illegal". An international court of law at the time wouldn't have been impartial either, as pro- and anti-monarchist sentiments were reeling at the time. Some wanted to restore the monarchies of Europe, and others wouldn't even think about it. Having Americans and Frenchmen judge not only Nicholas II, but Wilhelm II as well, would have brought up a problem of impartiality because both the American and French mentalities excluded the monarchy as a form of government, so there would have been bias against the Emperor(s).
4. Who knows what pressures mounted on King George, as he didn't stick out his head for his cousin and look-alike. Perhaps he didn't want to undermine his own position as King of England, perhaps he felt that this would further alienate the Kaiser, who would probably get back to him with revenge once the war with Russia would be over, who knows. From our point of view he was wrong, and it is sad to see how those who were close to Nicholas II in his best moments, wouldn't achieve anything to at least, save his children from a certain death.
5. In politics there are no friends, just interests. I doubt that even with a fair trial, Nicholas II would have been allowed to leave Russia, as the stakes for a restoration of the monarchy were high at the time. That is why the short, bald man with his ridiculous beard had the IF shot.