In Cura 2.4.0 with the following settings I get only support on Z layer 1:
0.3 mm layer height
Support Enabled,
Build Plate Adhesion Type: None,
Layer one only prints supports, no part paths are generated. Layer two has part paths and support paths. This leads to a 3D print that does not stick well to the build plate due to layer 1 not having part data. Seems like a rounding error or oversight for thicker layer height printing, sine these same settings work in Cura 15.04.
See the attached image from Cura 2.4.0, Layers View Mode, showing layer 1 with only support paths.