Not sure what you mean by "import numbered stills". All version of MEP easily import stills. If you mean will MEP assign a number to them as they are imported, I'm not aware of any version that will do that. The files come in with their original names.
In some 3D applications like Maya the production is not exported in a video file format like .avi or .mov but in individual images at a frame rate of e.g. 24. So in many video editors like Adobe Premier you can import video files like .avi or you can import a "number of still images" that make up the motion changes at a rate of 24 frames per second or whatever the out put was. Premier does this import automatically but Magix does it if you set up your still image to display at 1 frame instead of the default 7 seconds and then when you play all these images they run like video footage. This seems to be the only way to do this but it should be a standard feature like the other editors have.
I don't use 3D so I didn't understand the concept. I appreciate you taking the time to explain.
It's a shame Magix doesn't have a "Whish List" section on this site like they did on the old forum where users could post features the would like to see in future versions of Magix products.