Save the below info as a macro and then run it through a batch process. You need to change the 'FILEPATH' to the path of your attaching reference, and 'FILENAME' to the name of your reference. This will just place the reference file in its default location.
Let me know if this works.
Ryan
Sub main
Dim startPoint As MbePoint
Dim point As MbePoint, point2 As MbePoint
' Start a command
MbeSendCommand "REFERENCE ATTACH "
' When a command brings up a modal dialog,
' a later statement must close the dialog,
' or the MbeState.modalDialogByUser property
' should be set to 1 so that the user must close
' the dialog when the macro is executed.
' Also, you may not use the debugger "Step"
' commands while a modal dialog is displayed.
' Opened modal dialog "Attach Reference"
MbeSendCommand "MDL COMMAND MGDSHOOK,fileList_setFilterCmd *.dgn"
MbeSendCommand "MDL COMMAND MGDSHOOK,fileList_setDirectoryCmd C:\FILEPATH"
MbeSendCommand "MDL COMMAND MGDSHOOK,fileList_setFileNameCmd FILENAME"
MbeSendCommand "MBE1 CLOSEMODAL OK"
MbeSendCommand "MBE1 CLOSEMODAL OK"
End Sub