Importing meshes/models across 3D modelling platforms is sometimes necessary in order for the creator to import their assets into Trainz or make use of various features available in different programs (e.g. bump mapping - not available in Gmax).
Various methods have been devised to move models across from one piece of software to another, but there is currently no program available to directly convert from one file format to another. Due to the nature of importing meshes from one program to another, some methods involve loss of detail, loss of texturing or loss of animation.
3DS Max>Gmax via .3dsEdit
3DS Max>Gmax or 3DS Max>3DS Max via BFF ExporterEdit
For users of 3DS Max v.7,8,9,2008,2009, the current lack of Trainz exporter has forced the use of a particularly useful freeware tool involving MaxScript to export and import between 3DS Max and Gmax freely. The BFF exporter and instructions are available at http://www.scriptspot.com/bobo/darkmoon/bff/ and although still in development allows complete transferability (minus animation) between two programs.