The function of the MXS Reference object is to allow you to link a Maxwell MXS file into your scene at export-time.
Path
This is simply the path to an MXS file. The geometry may be scaled and positioned as usual via the Coord. tab. When an MXS file is loaded, it may be opened in Maxwell Studio by clicking the Studio-icon button.
Display
These parameters determine how the reference geometry will be represented in the C4D viewport. Depending on the nature of the geometry, it may be desirable to use bounding boxes (one is created for each mesh in the MXS), or points, which are taken from the mesh vertices contained in the MXS file. Use the detail parameter to control how many points are drawn:
 |  |  |
| Source MXS | Detail: 10% | Detail: 100% |
Notes
Objects contained in MXS files are always defined in terms of a meter scale. In C4D, however, an arbitrary scale factor may be in effect. For example, consider an MXS file which contains a one-meter cube, centered at 0,0,0 in space: it has vertices at +/- 0.5 in each quadrant. If this MXS is referenced while C4D's units are set to meters, these coordinates will mean +/- 0.5 meters in C4D, just as they do in the MXS file. If, on the other hand, C4D's units are set to millimeters, these coordinates will have a different meaning: the cube will appear to be 1 millimeter in size. In order to represent the cube at its natural size, as defined in the MXS file, one would need to scale the MXS Reference 1000x using the scale values in the MXS Reference object's Coords tab.
To help with this, the plugin queries the current units setting whenever an MXS Reference object is created, and pre-sets its scale values to make it appear at the correct size in the context of the current C4D unit system. If the C4D units are subsequently changed, the MXS reference will naturally maintain its current size with respect to the other objects contained in the scene. When the document is exported, depending on the Scale Units setting in the exporting Scene Object, the size of all MXS references will be scaled as necessary, in order to obtain a WYSIWYG result.