Cannot Change Level Display in DWG Reference

Hi Everyone,

One of our users has reported an issue while attempting to adjust the level display of a DWG reference file. 

All the reference levels are grayed out and cannot be adjusted. This occurs when the DWG file is attached

to another DWG file. If the DWG file is attached to a DGN file there is no issue and one can adjust the DWG

reference levels display. This happens in Microstation SELECTseries 4.

Any ideas?