My wife and I are currently separating. We bought our house together in 09. She put the down payment down.

The house is community property but the other party is entitled to reimbursement for their separate property contribution to the down payment. So...

What is default against a man for paternity and calculating child support?

Default means the other party has failed to respond after 30 days of being served with the summons and petition.

Can you still be able to have a divorce without the other parties signature?

If you cant find them to serve them, you need to serve by publication. Consult with an experienced family law attorney.

Can you win on appeal based on the other parties lack of response?

No, even if there is no response they will determine the case on the merits of the argument.

If you are talking about the response to petition, you can serve the attorney by mail.

Status hearing with a marital agreement.

probably not, the judge will ask you about the status of the case and you will tell him that you submitted the judgment with the MSA attached, the...

When does the 6 month waiting period for divorce begin in California?

The dissolution can be entered in six months and one day after the service is complete; i.e., when the newspaper submit an affidavit of publishing...

Family law. Can i do an ex parte hearing. Child custody status hearing coming up.

Ex parte will only be granted if there is some sort of imminent harm. From the facts you have provided this would not qualify.

Do I file my divorce under my name on the marriage certificate or my current legal name?

Current legal name. You can request to have your name restored however.

Default judgement with marital agreement. Spouse is active duty.

You can proceed by default without him being there if he did not respond.