This link should answer all of your questions about NZ Firearms requirements. http://www.police.govt.nz/service/firearms/index.html
No they do not. There is no state where it is a legal requirement.
There is no legal age to own, but you must be 18 to buy one.
Indiana does not have gun registration. If you're carrying your firearm in the legal and prescribed manner, there is no requirement for it to be registered.
What is the "legal paperwork" you seek? In most of the US, there is no requirement for registration of ordinary firearms. A few states DO have such a requirement for SOME guns. We need to know what state, what gun, and what you are looking for.
Gun laws are dependent on your State. In Texas there is no requirement to register or license guns. A person who carries a gun on their person must have a Concealed Handgun License (CHL), but not the gun itself. It's legal to have a gun in your car without having a CHL.
legal requirement
There is no legal requirement in the US for any organization to be "diverse"
in MOST of the US, there is no requirement to register a gun.
Typically, no.
There are semiautomatic versions of the Tommy gun (Thompson sub-machine gun). They are legal to own. A fully automatic Tommy gun is legal in Texas only if you have the federal license.
There is a legal requirement to pay back legal aid in the country of New Zealand. When the person receiving the legal aid has lied about their financial situation, they are required to repay the legal aid provided.
15.