License often grants usage for animation and renders. It is often okay to create add-on items or textures for a product - always a good idea to contact the author first if in doubt. Creating a low-poly version to use in a game is derivative. Also taking that dervative and putting it into a game where others could potentially cache copies of that item is redistribution, whether or not the intent is there. I don't know if the sims2 handles it that way (by caching copies) or if it's multiplayer only. In a standalone game it may be a bit different but it's still questionable. Using the logic of poly-reducing the object and reshaping the UVs is okay... So if I bought this person's hair model, reduced the polygons to the point where all the coordinates had moved then put it up in freestuff, that's okay? I don't think so. If I didn't have the hair in the first place, I couldn't have done this as I derived my new hair from the original. It would have probably taken me less time to model something from scratch than to find a bunch of loopholes to work around in trying to distribute something made by someone else. I find this to often be the case.

.