This manual explains what vertices, edges, faces, and meshes are in the context of Sweet Home 3D.

What is the MTL file and what are all those weird values? This manual explains it.

What are levels and how do you calculate new elevations and heights? This manual explains it.

This manual explains how to change material names in obj and mtl files. This is important when you are creating furniture in Sweet Home 3D and want to assign meaningfull names to parts of your model. The zip file contains the Sweet Home 3D project and the obj/mtl files used in the manual.

This manual explains how you can add animated gif images as layers in Sweet Home 3D renderings. Besides Sweet Home 3D you will need Image and Video software.
All the research, experimentation, image creation, and the endresult video are the excellent work of GaudiGalopin3324. I just created the manual from multiple forum posts in cooperation with GaudiGalopin3324.

This manual explains how to create Bifold Doors. The manual explains step-by-step how to create the doors, change the material names, and add the deformations so the doors open in Sweet Home 3D.

A few manuals still in development: Creating Furniture for Beginners, How-To Create windows, Move and align objects, The OBJ file explained.