The popupmenu is easy
VB Code:
  1. Private Sub MSFlexGrid1_MouseDown(Button As Integer, Shift As Integer, x As Single, y As Single)
  2.       If Button = vbRightButton Then
  3.          PopUpMenu mnuMyMenu
  4.      End If
  5. End Sub
I think you will need to do a left click for the hightlight, and then a right click for the menu.