SDFlexGrid1.SetCellCustomize(0,0,xui.Color_White, xui.Color_Black, xui.CreateDefaultBoldFont(8)) affects on "top-left" cell of table, but not on header. I had try put row number -1 instead of 0 (just in case, who knows...). But naturally got error message from debugger.
It's easy to change name of column, which is text in header, but I jam with header's font size.