*Leaf*: It sounds like you're in the right mindset for the Con. Nice melodic shapes (if rather simple), and unique choices of timbre reflect well. Knowing how to use computers in the compositional process is also a plus. I can't say without looking at your audition portfolio, but based on the page, I'd like to see greater variety in performance media: writing for different ensembles, utilising different (contrasting) compositional techniques.
A couple general words of advice for anybody considering applying for Composition at the Con, or any other tertiary institution:
1) Explore different compositional styles in your portfolio. Use contrasting ensembles and/or extended techniques, and choose pieces that you feel show the most variety in your compositional output. This is not the HSC - you're not writing to time limits or specific performers, so don't limit yourself.
2) Presentation is key. Markers are looking at your ability to convey your ideas to your performers. Your scores should be neat (try and make your scores look like the ones you see in those expensive music books), printed clearly (laser printer, people), and properly bound. The markers are far better trained to spot mistakes in your scores than a HSC marker, so scores should be carefully proofread, with musical notation and expression used appropriately. Program notes and performer instructions should be included where appropriate, and should be written in the best English you can possibly muster.
3) You are competing against other talented composers for places. The markers are not just looking for competent composers, they are looking for those who they feel will most benefit from the course. They are looking for candidates who stand out from the crowd - those doing something inventive and unique, who demonstrate a drive to really push the boundaries of Australian music. Even if you get in, you will not benefit from the course if you are closed-minded to different musical ideas, and insist on only writing music in the style of 18th century lieder.