No, the UMAT was fine. There is no maths section as such, just a subsection of really easy mathematical reasoning in the first logic section. If you're an extension 1 or 2 student it should be easy for you. As long as you have practice questions, you should be able to do it no problem. I think i did a total of 45 minutes study for the thing in between school and home on the train one afternoon. Just familiarise yourself at the types of questions, and practise answering them quickly.
The interview stage...well I only applied for UNSW, so I can't talk about interviews in general. Any specific questions?
Stats...well last year over 3000 applicants locally...300 first round interviews for 160 local places, 220 undergraduate places overall this year.
My UAI was 99.85.
Yes, you are right about the science-related course. But that's jsut to get into undergraduate med. Many people do med sciecne, althogh I'm not sure if that's wise becuase most people doing the course are only doing it to transfer, so the competition's very fierce.
The GAMSAT applies for all universities that offer medicine to graduates. So sydney uni would be among them. but many other universities recognise GAMSAT - it's just the graduate version of UMAT, although the exam is very different. you only have to do the GAMSAT if you have completed a degree (not done one year of one, and want to transfer) and want to get into medicine.
hope that helps.