I'm not sure your code is correct anyway. It looks as if it will give you the first items in your listbox to the number of items selected.
to illustrate
a
b(selected)
c
d(selected)
e
your code would return a and b (if you had selected three items it would return a,b,c)
You need to have the code tell you which items where selected.
try this instead:
Dim count As Long
count = [List0].ItemsSelected.count - 1
ReDim myarray(0 To count) As String
With [List0]
For x = 0 To count
myarray(x) = .ItemData(.ItemsSelected(x))
Next x
End With
For y = 0 To count
Debug.Print myarray
Next y
If my thinking is incorrect feel free to let me know.