As a DLC on Steam, there is no mod sources button. How do you do this?To create a mod, first run tModLoader. Click on the "Mod Sources" button in the main menu, then click on the "Open Sources" button to open the folder which contains your mod sources. In this folder, create another folder for your mod, then put all of your .cs files and .png files in that folder. When you are done, build your mod from the "Mod Sources" menu . If the mod failed to build, the game will show you one compile error, and give you an option to view all compile errors as a text file. If the mod successfully builds you will be returned to the main menu. If the game crashes or a mod fails to load, the game will display the error and also give you the option to view the error as a text file. Mods that crash on loading are automatically disabled. Mods are automatically enabled when they are built.