I'm having the exact same issue here using v8.1 of the WinGrid. Basically, display layouts cannot be loaded to the grid when I use conditional formatting on the columns. I get the "Exception has been thrown by the target of an invocation." exception.

Sample code (with oColumn being a column in the grid and ultraGrid1 being my grid):

ConditionValueAppearanceForm conditionValueAppearanceForm = new ConditionValueAppearanceForm( oColumn );
DialogResult result = conditionValueAppearanceForm.ShowDialog( this );
if ( result == DialogResult.OK )
{
    // If the user clicked OK, set the ConditionValueAppearance on the column.
    oColumn.ValueBasedAppearance = conditionValueAppearanceForm.ConditionValueAppearance;
    ultraGrid1.DisplayLayout.SaveAsXml( "layout.xml" );
    ultraGrid1.DisplayLayout.LoadFromXml( "layout.xml" ); // This throws the exception
}

If anyone has any ideas here, it would be greatly appreciated. I created an incident report already. I'm expecting my users to create their own simple or complex profiles, so I need the intended behavior. I have it so that a user could filter Column A and then set up formatting so that when Column B has a value greater than 0, Column A would show up with a background color of red. I can save that layout fine. But, I need the grid to have that view the next time he/she opens the application, and that's where the exception occurs every time. The exception goes away if I remove the conditional formatting from the column.