1. In MicroStation, open the Level Manager.
2. From the Level menu, select Import... to obtain the Import Levels panel.
3. Select the desired Level Library file (.CSV).  NHDOT users will find all standard Level Libraries at N:\cadd\cadd\V8Workspace\Standards\dgnlib\.  Users outside NHDOT can download them from the NHDOT File Library. They are stored in nhdot-msv8-dgnlib.zip.  Refer to Drawing Names for the proper Level Library assignment for each NHDOT standard drawing.
4. Click OK to return to the Level Manager panel.

5. Click on the Update Levels button (the rightmost of the 3 buttons), this will set the correct default values for each level in the drawing.

By Importing the level library the levels are actually created in the .dgn file and can be seen and shut off when attached as a reference file.  If the library file is attached the levels are not actually created and cannot be manipulated when referenced.  If the Level Name is displayed on the Level Manager it identifies the Level Library [contained in brackets] from which the level was attached.  If you see the name in brackets the library should be detached (which erases attached unused levels) and then imported to actually create the levels. 
Levels that are out of the number sequence probably don't belong in that dgn or are drawn in the wrong level and should be moved to the correct level or the correct drawing, then delete the empty level.  

1. From the Level  Manager, select Level => Library => Detach... to obtain the Libraries panel.
2. Select a Level Library file (.CSV) from the middle portion of this panel.

The selected Level Library will highlight, as well as display in the Name: box.

3. Click OK to detach the Level Library and return to the Level Manager panel.

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