Ribbon and Custom Task Panes

to add custom task pane. on ThisWorkBook.cs
private void ThisWorkbook_Startup(object sender, System.EventArgs e)
{
this.ActionsPane.Controls.Add(new ActionsPaneControl1());
}
to add custom ribbon RIght click project ->add new item->ribbon visual designer.
Everything you add there will be on the Addins Menu when you F5(run).
You can eliminate any other menu on the sheet/workbook. By setting your custom ribbon property ->Start From Scratch ->TRUE
so there's only your menu showed up.
Whualla .. piece of cake