How would you model a medieval castle? What should be done in a 3D package (e.g. Maya) and what in ZBrush? I know I need the detail from ZBrush, but I don’t know the workflow.
If I bring the whole model, it has one about face per wall, and it’s a heavy model (file size), how do I add detail to walls and edges (building stones and decay)?
Check this out: http://pixologic.com/zclassroom/lesson/projection-master-with-sebastion-legrain-introduction
But you will need sufficient polygons to support the details. Of course, if your intent is to use the model in an animation package you can certainly break it up into smaller parts, applying UV mapping to each part. Then you can subdivide as necessary in ZBrush to support the details before finally creating displacement and/or normal maps that you would export back into your animation program.