In the BizObjForm's SetPrimaryBizObj is the following code:

LPARAMETERS toBizObj

*-------------------------------------------------
*--- Store the specified business object reference
*-------------------------------------------------
This.oBizObj = toBizObj

IF This.oBizObj.lNoRecords
This.SetFilePos('NORECORDS')
ENDIF


Should not the lPrimaryBizObj Flag also be set? And the forms oPrimaryBizObj property as well? Maybe something like this:

IF !ISNULL(This.oPrimaryBizObj) AND TYPE('This.oPrimaryBizObj') == "O"
This.oPrimaryBizObj.lPrimaryBizObj = .F.
ENDIF

This.oPrimaryBizObj = This.oBizObj
This.oPrimaryBizObj.lPrimaryBizObj = .T.

should be added.

Maybe its a matter of intrepretation. I thought SetPrimaryBizObj would change the oPrimaryBizObj and set the lPrimaryBizObj flag.