Hi Katy,
When I posted this, I used the Esri Maps for SharePoint 3.0.1.
At that point I just participated the Portal for ArcGIS workshop in Sigapore.
I tried to chech publishing function to Portal at that workshop.
But I couldn't.
With the beta version, I don't still try with Portal.
(Offcourse I federated ArcGIS for Server properly.)
Could you publish the SharePoint list layer to Portal with EM4SP 3.0 or 3.0.1?