Need help applying ComboBoxes to my program

I'm creating a diving competion program that

1. keeps score for up to 16 divers.

2. Each diver has 8 dives.

3. There are 8 judges scoring each dives w/scores ranging from 0-10 w/one decimal place.

4. Each dive has a degree of difficulty from 1-4 w/two decimal places.

5. To get their final scores, throw-out the highest & the lowest and then add the remaining 6 and multiply by the degree of difficulty.

I would like to put the scores in a Simple DropDownStyle ComboBox instead of the text file where I have the names as hown below.

Code:

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Imports System.IO

Public Class Form1

    Shared difficulty As Dictionary(Of String, Decimal)
    Dim splashes As List(Of Splash)

    Class Splash
        Property DiverName As String
        Property DiveType As String
        Property Scores As List(Of Decimal)

        Function FinalScore() As Decimal
            'TODO: check there are enough scores for this to not throw an exception
            Return CDec(Scores.OrderBy(Function(x) x).Skip(1).Take(Scores.Count() - 2).Average()) * difficulty(Me.DiveType)
        End Function

        Sub New()
            Scores = New List(Of Decimal)
        End Sub

    End Class

    Private Sub SetUpDifficulties()
        difficulty = New Dictionary(Of String, Decimal)
        difficulty.Add("Bellyflop", 1D)
        difficulty.Add("Cannonball", 1.2D)

    End Sub

    Private Sub LoadData(src As String)
        splashes = New List(Of Splash)

        Using sr = New StreamReader(src)
            While Not sr.EndOfStream()
                Dim thisDive = sr.ReadLine
                Dim parts = thisDive.Split(","c)
                If parts.Length = 10 Then ' checks there is the correct number of elements
                    Dim thisSplash = New Splash
                    thisSplash.DiverName = parts(0)
                    thisSplash.DiveType = parts(1)
                    Dim scores As New List(Of Decimal)
                    For i = 2 To 9
                        scores.Add(CDec(parts(i)))
                    Next
                    thisSplash.Scores = scores
                    splashes.Add(thisSplash)
                End If

            End While
        End Using

    End Sub

    Private Sub ShowScores(sender As Object, e As EventArgs)
        Dim cb = DirectCast(sender, ComboBox)
        Dim theDiver = cb.SelectedItem
        Dim lines As String = ""
        ' iterate over the dives for a named diver, ordered by the name of the dive
        For Each s In splashes.Where(Function(d) d.DiverName() = CStr(cb.SelectedItem)).OrderBy(Function(d) d.DiveType())
            lines &= String.Format("Dive: {0} Score: {1}" & vbCrLf, s.DiveType, s.FinalScore().ToString("0.00"))
        Next
        TextBox1.Text = lines

    End Sub

    Private Sub ShowDiversNames()
        ComboBox1.Items.AddRange(splashes.Select(Function(s) s.DiverName).Distinct().ToArray())
        AddHandler ComboBox1.SelectedValueChanged, AddressOf ShowScores

    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        SetUpDifficulties()
        LoadData("C:\temp\dives.txt")
        ShowDiversNames()

    End Sub

End Class

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I experimented with creating 2 Simple DropDownStyle ComboBoxes in a new form to allow only up to 3 numbers including a period as I need the scores to be 1-10 w/1 decimal place but in doing so, I'm unable to use the backspace or delete buttons. Also, is it possible to force a period so that everytime I type in a number, a period is automatically inserted?

Code:

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Public Class form1
    Dim DSep As String = "."


    Private Sub ComboBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles ComboBox1.KeyPress
        If Char.IsNumber(e.KeyChar) = False And Microsoft.VisualBasic.AscW(e.KeyChar) <> 46 Then
            If e.KeyChar = CChar(DSep) Then
                e.Handled = True

            ElseIf Microsoft.VisualBasic.AscW(e.KeyChar) = 13 Then

                Me.ComboBox2.Select() ''<---jump to next text box after press Enter

                e.Handled = False

            Else

                e.Handled = True


            End If

        End If

    End Sub

End Class

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Any help is greatly appreciated!!!