I downlaoded an .OBJ file from Turbosquid but am getting an error message when I drag and drop "Unable to Import Model". I'm not sure why this would happen as OBJ is a file format accepted by Dimension.
Adobe Dimension can export/import obj file, but there is a problem with your file for Dimension as well for Adobe Stager. I am not able to open it.But I can view it in Microsoft 3D viewer and Adobe Modeler.
Can you try this:
Create a simple object in Dimension.
Export that object as OBJ from Dimension.
Then try to re-import the created file into Dimension.