Error message when importing an .obj file as a volume

Operating system: macOS
Slicer version: 5.2.1
Expected behavior: I’d like my 3D skull .obj thats been edited in C4D to be imported into 3D Slicer as a volume so that I can threshold it and then use WrapSolidify to extrapolate the inside
Actual behavior: When I upload the .obj through Add Data it imports as a Segmentation but when I try to import as a volume it gives me an Error Message with no information.

You should be able to export your segmentation to a binary labelmap volume and then convert that to a scalar volume if needed. But if it’s started as a surface model you won’t be able to threshold it since there’s not continuous tone values, just inside/outside the model. WrapSolidify should work though.