[Arculis]

I understand how to texture models using Lithium Unwrapper alright, but I don't understand how you can get different levels of detail, based on the same model, while using the same texture for each model (or resized versions of them).  Is there some way to do this, or do you just have to create individual textures for each level of detail?

[HotSnoJ]

You just need to map the lod somewhat like you did lod0. That's all.

[KARMA]

just start with already uvmapped lod0 and weld verts to reduce pcount and remove details.
Some uvmaps will get screwed but if you know what to do you won't have much new uvmapping to do