Yes you can serve as is without a file-stamp.

Yes you can amend before a party has answered and then serve the amended complaint.

How to serve/notify opposition of motion(s)?

You don't have to serve your motion if you don't want to. But if the motion isn't timely served then your motion may not be heard.

The courtesy tray outside a courtroom?

It's a courtesy copy for the judge.

Can I still sue for willful unlawful of my previous employer fired me ?

If you entered into a settlement agreement, you most likely agreed to settle and release all claims, whether known or unknown.

Im the primary parent my ex still hasnt came to a visit since court

Unfortunately, you can't make a parent be a parent. Best is to file for a child support modification. You'll be surprised what an increase in...

When a motion to compel is later a mediation date, can the lawsuit still be settled at mediation??

If a lawsuit is settled at mediation, you don't have to worry about future hearings such as a motion to compel.

What can be done legally and financially?

I suggest you consult with an attorney. There may be various claims you can assert in a lawsuit.

Can I sue a lawyer who now represents my ex husband but was getting paid with community money for 16 years?

I think there may be a basis to disqualify the lawyer.

My son has split up with girl friend of 12 yrs and have 4 kids together ages 6-12. Not married. who has to pay child support

Child support is based upon time share and income. A person that is unemployed may still be ordered to pay child support.