Using Foreign Keys in 8 Beta

[Transmission Man]

I've created a data model diagram that contains two tables. Each is set to use SQL Server 2005 as database type. Each has a table space name provided.  I draw an association from Table A to Table B.  When I right click on the association, and select 'Foreign Keys' the dialog opens fine.  The help file shows that columns from both source and target would appear in the FK dialog, but I only get the PK from the source (Table A) though there are columns, including PK, in Table B.  

Am I missing something or is this a bug?