[c#]
public class AdvFlyGrid : FlyGrid
{
  public virtual void SelectCell(NodeBase node, Column col)
  {
    if (node != null && col != null)
    {
      int colIndex = this.Columns.GetColumnCellIndex(col);
      if (colIndex != -1)
      {
        this.FocusNode(this.ActiveRootPort, node, colIndex, true);
        this.Selected = node;
      }
    }
  }
}

[c#]
//this handler gets current selected node, selects next and focus
//cell on second column
private void button2_Click(object sender, System.EventArgs e)
{
  NodeBase node = virtualGrid.Selected;
  NodeBase next = node.GetNext() as NodeBase;
  //if next node is null (selected node is last node), we get first
  if (next == null)
    next = node.Owner.GetFirst() as NodeBase;
  if (next != null)
  {
    virtualGrid.SelectCell(next, virtualGrid.Columns.Items[1]);
  }
}

[c#]
private int curColumn = -1;//start position
private void SelectNext(FlyGrid flyGrid)
{
  NodeBase node = flyGrid.Selected;
  bool selectNextNode = false;

  if (curColumn == -1)
    curColumn = 0;
  else
  {
    curColumn++;
    if (curColumn >= flyGrid.Columns.VisibleColumns.Length)
    {
      curColumn = 0;
      selectNextNode = true;
    }
  }

  NodeBase next = node != null ?
    selectNextNode ? node.GetNext() as NodeBase : node :
    flyGrid.Rows.RootNode.GetFirst() as NodeBase;
  
  //if next node is null (selected node is last node), we get first
  if (next == null)
    next = node.Owner.GetFirst() as NodeBase;

  if (next != null)
  {
    flyGrid.SelectCell(next, flyGrid.Columns.VisibleColumns[curColumn]);
  }
}