The MS3D Export Options window is displayed when you save a model in MS3D format. It allows you to specify how you want bone joint influences to be saved.
The Format Subversion options specify which MS3D subversion you want to save as. If no vertices in your model are assigned to more than one bone joint, select Subversion 0. Otherwise, select Subversion 1 or 2.
The Subversion Options section includes options that only apply to specific subversions. The Vertex Extra option is 32-bit number that is saved with the vertex data in Subversion 2. The number is specified in hexadecimal. The number supplied is used for all vertices. There is no way to set this value for individual vertices.
Click Ok to save the model with the specified options or click Cancel to ignore any changes.