Last year they just sent them out and somewhere around the middle of the year they sent out our half-way for this year. So, should be around the same time that the marks for the HSC come out. But, our teacher was going to mail us our marks when she finished getting them together, just to be nice.
The weighting for assesment to exam is 50/50. The 50 for the assesment is made up of the assesments and "proof" work that was done throughout the year. Proof work can also be used if someone has an epic fail in the exam, to show that they are capable of doing the work. So, you should be fine.