I just stripped away everything about the query except what's involved
with the problem here and the query ran (wow!) _BUT_ the calculation
returned "-1" for EVERY record with a UOMType "VOL" value! It
calculated properly for UOMType "WT" values!

Here is the query's SQL:
SELECT qryPKProfilesAssociationsPKWTsFGsULDims.txtProfile ID,
tblProfiles.Version,
qryPKProfilesAssociationsPKWTsFGsULDims.UnitCount,
qryPKProfilesAssociationsPKWTsFGsULDims.SubUnitCou nt,
qryPKProfilesAssociationsPKWTsFGsULDims.UnitSize,
qryPKProfilesAssociationsPKWTsFGsULDims.UnitUOM,
qryPKProfilesAssociationsPKWTsFGsULDims.UOMType,
qryPKProfilesAssociationsPKWTsFGsULDims.UnitSizeCt ,
qryPKProfilesAssociationsPKWTsFGsULDims.UnitSizeCt c,
qryPKProfilesAssociationsPKWTsFGsULDims.UnitSizec,
qryPKProfilesAssociationsPKWTsFGsULDims.Densitylbg al,
qryPKProfilesAssociationsPKWTsFGs.SumOfSumOfSUBUNP RODWtlb AS
SUBUNPRODWt,
qryPKProfilesAssociationsPKWTsFGs.SumOfSumOfSUBUNP RODWtlbTotal AS
SUBUNPRODWtTotal,
qryPKProfilesAssociationsPKWTsFGs.SumOfSumOfUNPROD Wtlb AS PRODWt,
qryPKProfilesAssociationsPKWTsFGs.SumOfSumOfUNPPRO DWtlbTotal AS
PRODWtTotal,
qryPKProfilesAssociationsPKWTsFGs.SumOfSumOfSUBUNP KWtlbTotal AS
SUBUNPKWtTotal, qryPKProfilesAssociationsPKWTsFGs.SumOfSumOfUNPKWt lb
AS UNPKWt, qryPKProfilesAssociationsPKWTsFGs.SumOfSumOfUNPKWt lbTotal
AS UNPKWtTotal, Round([UnitSizec]*[lbConvFactor],6) AS UNNtWtConvlb,
Round([UnitSizec]*[galConvFactor],6) AS UNNtWtConvgal,
IIf(IsNull([SubUnitCount]),[UnitCount]*[PRODWt],
[UnitCount]*[SUBUNPRODWtTotal]) AS UNPRODNtWt, Nz([UNNtWtConvlb],
[UNNtWtConvgal]*[Densitylbgal]) AS UNNtWtNz, Nz([UNPRODNtWt],
[UNNtWtNz]) AS UNNtWtNzc, Round([UNNtWtNzc],6) AS UNNtWt,
IIf([UOMType]="WT",Round([UNNtWt]*0.05+[UNNtWt],6) Or
[UOMType]="VOL",Round([UNNtWt],6)) AS UNEstNtWt
FROM (qryPKProfilesAssociationsPKWTsFGsULDims INNER JOIN tblProfiles
ON qryPKProfilesAssociationsPKWTsFGsULDims.txtProfile ID =
tblProfiles.txtProfileID) LEFT JOIN qryPKProfilesAssociationsPKWTsFGs
ON qryPKProfilesAssociationsPKWTsFGsULDims.txtProfile ID =
qryPKProfilesAssociationsPKWTsFGs.txtProfileID;

Any ideas why "-1" would result for WT values???

THANKS!!!