Automatically Create Worksheet ComboBox Based On Selection

I am working on a spreadsheet for a client. I am using Excel 2007 and she is using Excel 2000. I have created a emplate for her to enter survey data into. Using the following code, I have created combo boxes for the drop-down menus so the client can tab from one cell to the next while entering data:

Option Explicit
Private Sub TempCombo_KeyDown(ByVal _
KeyCode As MSForms.ReturnInteger, _
ByVal Shift As Integer)
'Hide combo box and move to next cell on Enter and Tab
Select Case KeyCode
Case 9
ActiveCell.Offset(0, 1).Activate
Case 13
ActiveCell.Offset(1, 0).Activate
Case Else
'do nothing
End Select
End Sub.....................