GIMP :: Scaling To Tiny Pictures

Just a question about scaling and pixelation. I've been doing some 3D models in ZBrush at a 960x960 size, and wanting to scale them down to 48x48 size, very small icons for a game engine.

Anyway I started doing this with just normal scale in GIMP, but the picture just turned out like a big blur. With further investigation I found GIMP add-ons, Liquid Scale and Step Scale (I think that was it's name) where you can step down the scale of the picture and sharpen it during step downs etc.

Still not having much luck, I can get it to look better, but not good, still very pixelated and blurry. The required result I want is something along these lines - Picture

Using high res picture, I've tried PNG, GIF, PSD with not really much luck.

PS: Attached is the original model GIF and the resized picture.