1. Under Hindu Marriage Act, "impotentcy" is not a ground for divorce. It is a ground for annualment of marriage, if there is no consumation of marriage due to impotency. That is not the case herein. The marriage is consumated. Hence marriage cannot be even annualed and divorce cannot be granted on that ground. The long cohabitation also prove there is no impotency. Further, She has to prove that she is virgin before asking the court to send you for medical test for proving your potency.
2. There is prescribed procedure laid down in Dowry prohibition Act to show that dowry is given and accepted. It is her responsibility to prove and she will fail to prove that dowry in the shape of jewellery was given.
3. You have to check up with Australian local laws about domestic violence. In India by giving false examples, she can file cases under domestic violence as well as dowry prohibition and Section 498-A cases and you have to contest them on merits. The 10% her parents paid for the flat, is her "Stri Dhan" and she is entitled to recover it and you have to pay 10% amount or sufficient compensation depending upon the situation.
4. You can file divorce case, if the marriage is solemnized in India on the ground of cruelty. If the case drags for years, both husband and wife come to mutual consent divorce and they will get the same.