Hi Nick - actually the objects from MoI do have layer information (all objects in a well-formed .3dm file must be on a layer), but they are all just on the "default" layer (except any layer info from objects opened from other .3dm files with layer info is preserved).

But I think you can automate the steps that Steve mentions to make a custom "Paste to current layer" mechanism in Rhino.

To do that set up an alias or keyboard shortcut in Rhino, and give it this:
_SelNone _Paste _ChangeToCurrentLayer

Or if instead of going to the current layer you want to see a choice of layers, try this:
_SelNone _Paste _ChangeLayer


Hopefully that will do the job.

- Michael