Just a word about converting 3ds files to obj files. There is nothing more annoying and frustrating than having spent a good deal of time converting models then, at a later date, when you go to use the converted model, the parts import scattered all over the place. This would be most disturbing after your trial period has expired when you become aware of it and can no longer reconvert. Before converting, click the utilities panel, the small tab with the hammer icon, and select the model and use the reset Xform. 3DStudio is a powerful, engineering grade precision CG package but does so in its own coordinate space environment. Many times while modeling we find it easier to mirror, clone, scale, move and do other transformations to symmetrical pieces but this action does not sit well with other programs using different space coordinate environments. Using the reset Xform (xform=transform) forces the model to behave in other programs.