Alias import question

[i777]

Hi
Just got hold of Keyshot 5.3 (having been a version 4 user). I just imported a file and for each layer (all of which had 'symmetry' ticked in Alias) Keyshot has produced 2 layers - one for each side of geometry. This never happened before - Keyshot always used to import exactly what I had in Alias (provided that symmetry was 'on' in the Alias layers and the layers I wanted were active/visible in Alias). Do I need to set up the import menu differently now?  - or do I have to apply materials in Alias and import by material type rather than relying on layers (which always worked great for me).?