JMB

Here's your UDfunction, after some close/open file and auto-debug from
excel, this work out for me
'--------------
Function mySP2(rng1 As Range, rng2 As Range, Optional dec As Long = 2)
mySP2 = Evaluate("=SumProduct(Round(" & rng1.Address(, , , True) & "*" &
rng2.Address(, , , True) & "," & dec & "))")
End Function
'-----------------
my quest is over for the function of sum of rounded products for 2 factors----
-----------------------------
i will post another thread for some more generic/productive
questions---maybe for 3 to 4 more factorial products...

i hope to receive more helpful reply from you
more power
driller