Could this be the reason?

Poser 13: A World of Possibilities - Poser - 3D Rendering & Animation Software (posersoftware.com)
Quote:
"Poser 13 is almost here, and we're excited to share with you some of the new features and improvements that will be included in this latest release. Unfortunately, end-to-end support for unimesh figures will not be included in the initial Poser 13 release. We understand that this is not ideal for content creators looking to seamlessly interchange data with other 3D design tools. To help with this, we have been working to improve Poser's design tools to simplify tasks such as creating clothing for figures. Fortunately, end-users creating scenes, rendering images and producing animations will not be affected and will find plenty of cool new features in this release."