After many requests, finally somebody from the community has encouraged to create a detailed tutorial about the process of creating addons, from botton to top. The document, created by Gauthier, covers all stages of the addons development process, from graphics to pak file creation, but it only uses pixel art techniques, not 3D.
This tutorial is basically written for pak128, but the process is the same for any pakset, the only thing that changes is the size of the images. It’s available at SNFOS site and we’ll try to include some parts in the official wiki.
Now you don’t have excuses to start creating new objects for Simutrans…. ;)