need help:three questions about HSMP

I have three questions.

1.My student visa will expire on 31st July, I will sent my HSMP application form next, If the HSMP approval come after the expiration of my visa,what should i do ?to extension student visa?

2. my MSC degree awarded will be further delay,due to the low work efficiency of my university, is there any alternative way?

3. the income point(25points) is vital for me. how to prepare document to improve the probability of success in this part

thanks