Marvelous Designer Support

I'm facing an issue that really doesn't help my workflow.

I'm often using the very useful Import OBJ to garment. But the issue is : as long as I work, the obj will retain its UVS. And if I export the simulated garment-OBJ, UVs are there too. Perfect. 

But if I save the scene, and re-open it, the OBJ doesn't have UVs anymore. Sometimes working with characters interacting, I find it easier, to simulate an animation using an MDD cache, to simulate each character separately, save a Zprj for each, then merge them once animation is simulated : to continue working later on the final pose with no more animation. But there again, UVs are gone.

Does someone know how to save a Zprj but KEEPING the UVs of imported Objs. I mean... Avatars I use are also OBJs imported but somehow they keep their UVs just fine, why not the garments from OBJs ? 

Thanks in advance for your help on that.