Private Sub cmdKey_Click(Index As Integer)
    cmdKey(Index).BackColor = vbWhite
End Sub

Private Sub cmdKey_MouseMove(Index As Integer, Button As Integer, Shift As Integer, X As Single, Y As Single)
    Select Case Index
        Case 0: cmdKey(0).BackColor = &HFF8080
        Case 1: cmdKey(1).BackColor = &HFF8080
        Case 2: cmdKey(2).BackColor = &HFF8080
        Case 3: cmdKey(3).BackColor = &HFF8080
        Case 4: cmdKey(3).BackColor = &HFF8080
        Case Else: cmdKey(Index).BackColor = &H8000000F
    End Select
End Sub

Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
    cmdKey(Index).BackColor = &H8000000F
End Sub