Howdy! My understanding is on the V3 codes were calculated by plugging your username into an equation with a preset number and the result was your code. So if my username was CHEEZ and my friend had a username that was BEANS, both of us would get a different code for the same item. If I had two V3s with the username CHEEZ, the code would work on both of them. If I accidentally typed in my username as CHEES I could play on the site, but codes I got wouldn't work. The website didn't exactly connect with it, just generate a code.
Souvenirs were gathered in a sort of scavenger hunt style. Clicking on certain objects could get you some, or completing objectives (ex: donating money to the king), or playing games on the site, or buying tickets in the shop on the V3 and typing the code it gives you into Tama Town.
