Few things then:
Because you have Dim ResultA inside the sub it will be reset to zero each time it runs
Place it OUTSIDE of the sub but in the same module then it will keep score
Dim ResultA
Sub AddtoPersonA
etc
If you name the textbox yourself rather than the default name it won't change when pasted
In 2007 you can do this in the selection pane in earlier versions you must use vba :
Sub Namer()
'select the first box and run this
On Error Resume Next
ActiveWindow.Selection.ShapeRange(1).Name = "MyBox"
End Sub
To add text on the current slide in the show
With ActivePresentation.SlideShowWindow.View.Slide _
.Shapes("MyBox").TextFrame.TextRange
.Text = ResultA
.Font.Size = 32
End With
Hope that helps
John