CAD volumes from Rhino file

https://www.dropbox.com/s/fu3u32b39oktc6f/rhino1.dxf?dl=0

https://www.dropbox.com/s/7hzxe1th8lgrpj3/cb1.skp?dl=0

I would like to create a .stp or .sat (ACIS) geometry file from either of the two files above.
If I export the file now, it gives me only one giant CAD volume. How do I split this into manageable volumes for mesh generation?

Thanks.