Oh sugar honey iced tea...
So if some how my model accidentally used this thingy you speak of... Then it wont work?
Basically-
>>Model something in 2.63
>>Save it
>>Open in 2.49
>>The model is now in wireframe form, all the faces disappeared with the edges being the only thing there.
>>Select entire model, and hit f-->Auto. Solidshade all faces, then proceed to recolor and fix parts of model.
It'll work, you'll just have to do twice the work.