In 3ds Max, go to MAXScript → Run script and navigate to the MZP file.
Or, Drag the MZP file into your 3ds Max viewport.
Click install and confirm any dialog boxes that appear.
Go to Customize → Customize User Interface → Toolbars.
In Category, select Klaas Tools.
Drag the Sketchfab icon to a toolbar.
The exporter is now available from this toolbar.
How to use
Open your model and run the script.
Enter a title at the top of the exporter panel and mark the model as
and/or Animation if necessary.
In the Light, bake, uvw panel, you can enable light baking and choose Auto unwrap objects if you haven't unwrapped the model yourself.
You can adjust Texture sizes with the Density parameter. If you select your objects and click Calculate sizes, you can see how many and what size textures your model will use. The maximum texture size is 2048×2048, so if you need more, it will create multiple 2048 textures.
Under Lighting type you can choose between Automatic (a generic soft light) and Manual (lighting in the scene). It supports Scanline, V-Ray, and Mental Ray. In all cases, it will use other render settings from the scene, such as sampling.
Fill in the Tags and Description.
Authorize the script to use your Sketchfab account.
Select your model, save it, and click Send selected objects to Sketchfab!
If you chose to Auto unwrap objects, you will see 3ds Max render the unwrapped textures. Then it will package the model and send it
to your account. When the upload is complete, you can view your model on Sketchfab (click Open model Name), adjust
rendering settings, and save the default view.