Ok done. For those who are looking for solution:
1. add custom ColumnOverrideLabelAccumulator with code like this:
@Override
public void accumulateConfigLabels(LabelStack pConfigLabels, int pColumnPosition, int pRowPosition) {
super.accumulateConfigLabels(pConfigLabels, pColumnPosition, pRowPosition);
if(_table.getGridLayer().getBaseBodyLayer().getSelectionLayer().isRowPositionSelected(pRowPosition))
pConfigLabels.addLabel("TEST");
}
and add custom theme based on "TEST" - label something in Your custom implementation of AbstractRegistryConfiguration, like this:
Style lCellStyle = new Style();
lCellStyle.setAttributeValue(CellStyleAttributes.BACKGROUND_COLOR, new Color(Display.getCurrent(), 100, 100, 100));
pConfigRegistry.registerConfigAttribute(CellConfigAttributes.CELL_STYLE, lCellStyle, DisplayMode.NORMAL, "TEST");