Layer States Manager 2010

To anyone with some helpful insight:

My office switched from LandDesk 2008 to Civil 2010 a few months ago and I personally have been working on a very large project (6,000 acre) resort project that has numerous xref files in each dwg sheet. We are having serious problems with the layer states manager...each time someone spends the time to get a drawing set up so it plots the way we want and saves the layer state in model space accordingly for future plots...all of that work seems to get lost when we close the file and reopen it later on. Layers that were on in the layer state are now turned off, colors of layers change, etc. I am certain it is not a visretain issue...has anyone else experienced severe layer state issues in civil 2010????

Help us please!