When I import the model in BrawlBox, it doesn't show anything in the Model Viewer. I know many people mistakes this as trying to export a model in Brawl, but that's not the same... Here are some screenies :

Opening up BrawlBox

Taking a random Brawl character file

Time to replace the old model

Here's my "Homebrew_Model" which is the one I have so much difficutly with.

Now that it's imported, let's preview it...

Blank!!! But the model's information can be seen at the left, and the model itself is perfectly viewable in 3ds Max, so...why I can't see it here?