Installing v1.9.XX and Downpour Mods:

If you own Rain World on Steam, these mods can be installed by locating them on the Steam Workshop, subscribing to the desired mod(s), and then launching the game and enabling the mod(s) through the Remix menu.

If you own Rain World on GOG/EGS or another PC platform, you will need to get a direct link to the mod. This is done by clicking any mod on the homepage of RainDB, and then selecting "Direct" download. This will download a zip archive containing the mod's contents. Once the mod is downloaded, navigate to the following directory within your Rain World game folder:

RainWorld_Data/StreamingAssets/mods

You will need to create a new folder in there for the mod you just downloaded. Then extract the contents of the zip archive into the folder you created.

For mod creators, this is where you will place your mods' directories while you are developing them as well.

引自RainDB

基本意思是把模组文件夹放在 RainWorld_Data/StreamingAssets/mods 里面。https://www.raindb.net有很多模组文件可以下载，但网站在外网加载很慢。一些QQ群可能也会有模组文件夹资源。总之，这个渠道不算太畅通，想玩模组建议还是用STEAM版本。