As for the German Weapons Act of 1938, a quick summary of it is easily found on Wikipedia (with primary sources cited as well for those wanting to vet the info)
The 1938 German Weapons Act
The 1938 German Weapons Act, the precursor of the current weapons law, superseded the 1928 law. As under the 1928 law, citizens were required to have a permit to carry a firearm and a separate permit to acquire a firearm. Furthermore, the law restricted ownership of firearms to "...persons whose trustworthiness is not in question and who can show a need for a (gun) permit." Under the new law:
Under both the 1928 and 1938 acts, gun manufacturers and dealers were required to maintain records with information about who purchased guns and the guns' serial numbers. These records were to be delivered to a police authority for inspection at the end of each year.
- Gun restriction laws applied only to handguns, not to long guns or ammunition. Writes Prof. Bernard Harcourt of the University of Chicago, "The 1938 revisions completely deregulated the acquisition and transfer of rifles and shotguns, as well as ammunition."
- The groups of people who were exempt from the acquisition permit requirement expanded. Holders of annual hunting permits, government workers, and NSDAP members were no longer subject to gun ownership restrictions. Prior to the 1938 law, only officials of the central government, the states, and employees of the German Reichsbahn Railways were exempted.
- The age at which persons could own guns was lowered from 20 to 18.
- The firearms carry permit was valid for three years instead of one year.
- Jews were forbidden from the manufacturing or dealing of firearms and ammunition.
On November 11, 1938, the Minister of the Interior, Wilhelm Frick, passed Regulations Against Jews' Possession of Weapons. This regulation, which only applied to newly conquered Austria and Sudetenland, effectively deprived all Jews living in those locations of the right to possess firearms or other weapons
So, pretty much everyone who was aligned with the government was exempt. The permit restrictions otherwise didn't change at all from the previous law of 10 years earlier. It only applied to handguns and not rifles/shotguns and Jews couldn't own firearms as well. It required a sort of passive registration as vendors had to keep track of who they sold guns to and surrender them to the authorities.
So, some of the previous statements made are true. No background check was required, hunters in particular were completely exempt, and I find no record that guns were classified in any way other than handgun vs long gun. It is true that those under 18 were not allowed to own firearms, but this is actually a loosening up of the previous law that restricted those under the age of 20. So that statement, while true, is a bit misleading.
Edit: Just as an aside, many of those regulations are still in place in Germany today.