Excel 2010 sucks almost as bad as Libre/Open Office Calc 5, so here are some notes:

macro_function.vba

Function example(ByVal r As Range, r2) As String
    ' Functioning practical Excel example by Cees.Timmerman@company.
    ' 2016-01-19 v1.0
    ' Sample usage: Press Alt+F11, Tools, Macros..., "example", Create, and replace template code.
    ' Make A1 "1;2;3" and B2 "=example(A1;A2)" or "=example(A1,A2)" if second parameter doesn't turn green.
    ' B2 should now have value "03". Press Ctrl+Alt+F9 to update all function cells after editing the function.
    On Error GoTo ErrorHandler
    Debug.Print "When debugging, this appears in the Immediate Window. It is now " & Now()
    Debug.Print "r is " & r.NumberFormat _
        & " " & TypeName(r) _
        & ": '" & r.Value & "'"
    parts = Split(r.Value, ";")
    result = Application.Text(CLng(parts(2)), "00")  ' CInt overflow merely causes "#VALUE!" without error handling.
    Debug.Print "Result: '" & result & "'"
    example = result
    Exit Function
ErrorHandler:
    msg = "Error #" & Err.Number & " in " & Err.Source & ": " & Err.Description
    Debug.Print msg
    MsgBox msg, vbCritical
    Stop  ' Manually Debug, Step Into (F8) thrice to highlight the statement after the error.
    Err.Clear
    Resume Next
End Function

Also note this shit:

x = Sheets("B2C").Cells(1294, "D")
debug.print typename(x)
String
set x = Sheets("B2C").Cells(1294, "D")
debug.print typename(x)
Range

And the fact that filters are ignored by default.