#138 is a rolling quadsphere avatar, derived from "Wengen Snowball." Its name refers to the first third-party region I rented, upon which I learned most of what I know about building. Add all the system clothing things in the product box, then add one of the two quadsphere objects. You can now roll around as you like. You can roll backwards, sideways, and at four different angles. If you're sat, or on a vehicle, you don't roll. That's all.
*NEW IN V1.2: PRIM ATTACHMENT SYSTEM. Now you can link random prims to your avatar and have them roll along with you! Refer to manual for info.*
The avatar contains two linked prims, the second of which is the quadsphere. The C/NM/NT script lives in the root prim. If you want to resize the snowball, adjust link 2 (snowball) and detach / reattach the avatar. If you're too tall or too short, adjust Z position.
The quadsphere may or may not have LODs. (It's been so long since I made it that I can't remember.) Root prim is... A prim. Cube, specifically. This being an avatar, rather than an an inworld decoration, you shouldn't expect physical miracles. (If you *must* use it as an inworld decoration, remove the script and fix the physics with a sphere prim.)
Resizing the mesh *will* change the LI. Probably shouldn't do that, yeah?
Be sure to read the product manual thoroughly!