This thread is like a car pulling a caravan that has started to wobble, with the driver trying to fix it by accelerating.
As the first one to question the 'dislikes' (in the other thread) I'll point out that I don't care about the likes and dislikes things that some forums have. I'd prefer it if people actually posted things. However it is odd to 'dislike' a post without saying what the problem is, and most of us like to help people make race tracks. It's reasonable to suggest a clarification.
Someone may be able to help you with your XPacker problem. The 'vertex' error suggests the object is too complicated, or malformed in some way. Try something simple, like a cube with one texture, and see how it goes from there.