To Attach a 1:100 A0 Border as a Reference

In the References dialog, select the Attach References icon.
The Attach Reference dialog opens.
Navigate to the ..\Default\Borders\ISO\ folder in MicroStation's program directory.
Select A0-border.dgn and click Open.
The Reference Attachment Properties dialog opens.
From the Models list box, choose 1;100.
Check that True Scale is turned on with Scale (Master:Ref) set to 1:1.
From the Nested Attachments list box, choose Live Nesting and set Depth to 1.
Click OK.
Enter a data point to position the reference.