Open Utilities > Plugin Manager and select import3DM to enable the plugin. The plugin will be listed under Autodesk Exchange Apps.
Select the Auto Load option to automatically load the plugin the next time Alias starts.
The plugin will be installed under the File > Import menu, as Import 3DM

Click on Import 3DM to open a 3dm file to a new stage or the current stage depending upon the option.
The following datasets are translated

The installer that ran when you downloaded this app/plug-in from Autodesk App Store will start installing the app/plug-in. OR, simply double-click the downloaded installer to install the app/plugin.

You can unload the plug-in without uninstalling it by unchecking the "Load/Unload" checkbox associated with the plug-in in the Autodesk® Alias® Plug-in Manager. You may have to restart Alias to completely unload the application.

Please ensure the following pre-requisites are met. 
.NET framework 4.6.1 or above. Download the framework from https://www.microsoft.com/en-us/download/details.aspx?id=49981 
Microsoft Visual C++ 2019 Redistributable or above. Download the files from https://aka.ms/vs/16/release/vc_redist.x64.exe

To uninstall this plug-in, exit the Autodesk product if you are currently running it, simply rerun the installer, and select the "Uninstall" button. OR, you can uninstall it from 'Control Panel/Programs and Features' (Windows 7/8.1/10/11), just as you would uninstall any other application from your system.

Limitations: Some trim edges might be distorted when importing certain Rhino parametric geometry.

• Work Around 1: If you encounter such distortions, an optional Rhino 6 Plugin and Rhino 5 Plugin are provided to correct those distortions.
  The plugin provides two commands
  1, DS_Optimize: This would optimize the geometry in Rhino for transfer to Alias and other neutral formats.
  2, DS_SplitKinkyEdges: This would split the edges at c1 discontinuities.
• Work Around 2: Save the file in Rhino as v2. The resulting files will not have distortions when imported to Alias