I do a lot of Sketchup work so here are my opinions:
Export objects as groups. Assign style colors as materials. All geometry and groups placed on Layer 0.
It is possible to also export geometry as locked groups, which can be safer but is not actually high on my list. When you import landscape geometry from Google Earth into Sketchup it comes in locked.
That's all; keep it as simple as possible.
Stay away from Layers. I have read that the only reason Sketchup has layers is because they knew they would have to import AutoCad layers somehow. Beginners can really screw up their geometry if they don't know how to use layers.
As the discussion has shown, edges, faces and vertices of two different objects can be stuck together if they get too close in Sketchup. This can happen between two objects that are on different layers if they are not grouped, even if one of the layers is turned off. So you can drag around all kinds of invisible stuff if you aren't careful. I don't use layers much. I prefer to hide/unhide groups and components in the Outliner.
It would be impractical to export objects as components because each component has its own axes. Well designed components require well placed axes which is a step you might as well take in Sketchup rather than an export dialog. It is easy enough to select a group and make it a component once it is imported.
unc
|