Studio Designer cannot export the floor reflection to any of the available output formats (TIFF, PDF, U3D and Collada).
Symptoms
When exporting files from Studio Designer (TIFF, PDF etc...), the file is exported correctly, but its not possible to export the floor reflection that is visible in the main window of the Studio Designer.
Solution
This feature is not available in Studio Designer, as floor reflection is currently only a visible aid in the Studio Designer window itself. See the workarounds.
Workaround
Studio Visualizer also has a floor reflection (or "table reflection") feature and this effect is kept when exporting to an image or movie.
Alternatively, you can also export an image from Studio Designer and manually add a reflection in Adobe® Photoshop®.