Well, I think R.A. duties, at least for engineering/comp sci grads, are
pretty much the same in U.S. universities. I don't know how Australian
immigration can assess it, really, except from the recommendation
letter. In my case, the letter that I obtained from my advisor says
that I did things like reading research papers, testing the techniques
described, coding algorithms for images, validating them on real-life
data, etc. The only "unusual" aspect, in my case, might be that the
project was funded by an external company, rather than directly by my
department.
I did read the occupational duties in SOL, but they're so broad that
anything can fit in them, IMHO. Since you have more experience in this
than I do, what does Immigration look for in those R.A. letters?
Another (minor) issue is this: I have the original letter my advisor
wrote for me, which I can scan for my electronic application. However,
he's changed to a different university since then, so the phone number
mentioned in the letter is no longer his. What can I do about this?
Should I attach some kind of explanatory note with his updated contact
information?

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