The next update will be on something a bit easier: Australia. However, I do have one thing to sort out first.
The leading nation in the poll I held on Australian colonization a while back was Portugal. After all, the Portuguese colony of East Timor is less than 600km from Australia. However, there is one major issue, that being that the Portuguese Empire was in a state of decline by the 19th Century. Portugal was no longer a global superpower like it had been centuries prior, but was now just a minor European nation, with it's colonial empire being a mere legacy. There is one counterargument, though, and that is the fact that the Netherlands, also in decline by the 19th Century (and facing a civil war ITTL) end up colonizing Western Australia ITTL. If the Dutch could colonize Western Australia, then I'm pretty sure that the Portuguese could colonize Northern Australia.