It is possible to import STL files (3D models) into Examine Pro using the CT module, you need to have a 3rd party program installed that is able to open STL files, the 3D viewer in Windows 10 works, or the free software “Meshmixer” which can be installed on any Windows version and is a bit more robust than the default Windows 3D viewer anyway.
Ensure the preferred app is set as the default app for opening STL files (Meshmixer does this for you during install) and the CT module is enabled in Examine Pro. In Windows 10 you can just right-click the STL and choose add to current patient folder, or you can import STL files in via import picture directory (doesn’t work via normal import). They will then show in the patient folder and you can double click to open them in the native software, they will appear in Examine Pro in the image library as below.
You shouldn't need to configure the CT module at all for this to work, it will use the Windows default program for opening STL files by default, if they wish to use the "Carestream Mesh Viewer" software to view STL files you will need to choose the "Use CS Mesh Viewer" option.