Hi,
When you import DWG file to Creo Schematics (or Export from creo schematics), the file include only graphical representation without any logical data. That mean : parameters, connectivity info and co-shapes relations will be lost as well.
In additon, there is probability that creo schematic will not support some graphical representation as AutoCaD ( for example, Creo schematics does not support fill of shapes-shape will be imported empty or with cross-hatch )
Regards,
Gaby