Asallamu alaykum.
A good analysis. I've had a headache for 3 years doing the Adelaide Islamic Calendar. I used MoonCalc last year to give a solid indication of when the moon *could* be sighted.
www.moonsighting.com has the software adn lots of interesting info. From the site:
QUOTE
Ramadan: The Astronomical New Moon is on Monday October 3, 2005 at 10:28 Universal Time. Looking at the visibilty curve one can understand that the moon is in the Southern Hemisphere. The moon is about 15 houes old and being too low on the horizon for North America will set in 14 min. after sunset on west coast. It cannot be seen in North America nor anywhere in East of USA October 3. On October 4, it will be visible in most of the world except most of Asia and Europe, where it will be 24 to 31 hours old and less than 2 degrees above the horizon, still not visible. In Europe and most of Asia, it can be seen even on October 5, when it will be 48 to 55 hours old. Accordingly, the first day of Ramadan will be on Wednesday, October 5, 2005 for North America and most of the world, Insha-Allah.
When you look at the graphics for 4th Oct, you can see the moon over Australia is only 20-25 hours when it sets. That *may* make it very difficult to see. I believe my calendar showing a Ramadhan start date of 4th Oct is incorrect. Indeed, I'd prefer to have times progressing from Maghreb, Isha, Fajr etc rather than start with Fajr as all calendars seem to. This is becase A) the day starts at sunset and

because of this, it would be a more logical view of the dates. Ie Ramadhan starts on the night (Maghreb) the moon is sighted but fasting starts the following morning.
Quite possibly, if the Imams stuck with a sighting then Ramadhan could be on the 6th here (as seen from a Fajr starting calendar). If they take the view of checking with countries to our West then the 5th could be the day.
Allah knows best.