I'm trying to set up a macro so that when a user alters the corresponding row
column D value, it auto-inserts the formula's into E, F and G columns to do
the maths.

This is so that if a user adds a row to the sheet they don't have to worry
about copy pasting formulas etc.

The below is what I have but nothing happens..... help!

Sub Worksheet_Change(ByVal Target As Range)

Application.EnableEvents = False

If Not Intersect(Range(Target.Address), Range("A:E")) _
Is Nothing And Target.Row < 1 Then

Dim r As Long
r = Target.Row

If Cells(r, "D").Value < "" Then
'Then

' the below adds in the formula in column E, F and G

Cells(r, "E").FormulaR1C1 =
"=IF(ISERROR(VLOOKUP(RC[-2],'FFELibrary'!C[-3]:C[-1],2,FALSE)),"",VLOOKUP(RC[-2],'FFELibrary'!C[-3]:C[-1],2,FALSE))"
Cells(r, "F").FormulaR1C1 =
"=IF(ISERROR(VLOOKUP(RC[-3],'FFELibrary'!C[-4]:C[-2],3,FALSE)),"",VLOOKUP(RC[-3],'FFELibrary'!C[-4]:C[-2],3,FALSE))"
Cells(r, "G").FormulaR1C1 =
"=IF(ISERROR(IF(RC[-1]=0,RC[-2]*RC[-3],IF(R201C4=Sheet1!R[-7]C[-5],RC[-1]*RC[-3],RC[-2]*RC[-3]))),"",IF(RC[-1]=0,RC[-2]*RC[-3],IF(R201C4=Sheet1!R[-7]C[-5],RC[-1]*RC[-3],RC[-2]*RC[-3])))"

End If
End If

Application.EnableEvents = True

End Sub