In some cases you do not want certain features shown in your legend of a map.
Setting the property of Thematics.IndividualValueTheme.Bins(0).LegendRow.Visible to false will not work in MapXtreme 6.8.
This is a known bug and there is no patch.
However when you create a ThemeLegendFrame based on this IndividualValueTheme you can hide items from the legend by
Legends.ThemeLegendFrame.Rows(0).Visible = false