Make sure to make backups regularly. The Path is: HDD:\Users\YOURUSERNAME\AppData\LocalLow\IronGate\Valheim

I've noticed there are a lot more bugs in this game that aren't really being reported / talked about. Maps/Terrain colors don't match up (often biomes don't match with what's shown on map or compass, this includes on that valheim world generator thingy but also on the map itself), irregular spawning of mobs on different islands (some spawn more than others and also, dunno if it's intended but, Trolls don't spawn at their caves but in random locations as well), Mobs spawn in areas even with workbenches spammed (someone told me this would prevent spawns but it doesn't.. maybe it's wrong info idk or it was changed), maybe i'm lucky but it's rather rare that certain progress isn't always saved on quitting the game but it IS when logging out so i'm doing that before quitting the game.