Map: The maximum number of possible data inputs to this node is 19

I have a map similar to (please ignore the actual data values as the structure is what I am interested in):

<Vehicles>
…
<Vehicle>
    <GoodGUID>c586d06a-a237-49b0-be55-ff6681515188</GoodGUID>
    <CounrtyOfOrigin>Japan</CounrtyOfOrigin>
    <YearOfManufacture>1997</YearOfManufacture>
    <Make>Toyota</Make>
    <Model>Estima</Model>
    <Variant>Lucida </Variant>
    <BodyStyle>4DR Wagon</BodyStyle>
    <CCRating>2438</CCRating>
    <Transmission>Auto</Transmission>
    <OdometerReading>101000</OdometerReading>
    <OdometerType>KMs</OdometerType>
    <NumberOfOwners>0</NumberOfOwners>
    <History>Ex-Overseas</History>
    <ExpiryDateOfWOF>2008-06-21T00:00:00.0000000+12:00</ExpiryDateOfWOF>
    <FuelType>Petrol</FuelType>
    <ColourID>Black</ColourID>
    <ConditionID>$500 – $1000 to spend</ConditionID>
    <EngineNumber>2TZ-562212</EngineNumber>
    <Chassis>TCR10-1269929</Chassis>
    <VIN>7A8H61P0707269929</VIN>
    <DrawBeamCert>false</DrawBeamCert>
    <RegFlag>Un-Registered</RegFlag>
    <RegistrationOverseasDate>1997    </RegistrationOverseasDate>
    <PreviousCountry>Japan</PreviousCountry>
    <DamagedAtImport>false</DamagedAtImport>
    <CauseOfRegistrationFlag>U</CauseOfRegistrationFlag>
</Vehicle>
…
</Vehicles>

That maps to a schema like:
<Method ID=”1″ Cmd=”Update”>
   <Field Name=”ID”>57003</Field>
   <Field Name=”GoodGUID”>f64532a7-cec4-4b9d-8cb5-0122434cf7f1</Field>
   <Field Name=”RefID”>464835</Field>
   <Field Name=”CustomerNumber”>70793</Field>
   <Field Name=”VendorCustomerGUID”>bc33e813-22f4-48d3-9597-42a25482bae3</Field>
   <Field Name=”ReceivedDate”>13/12/2007</Field>
   <Field Name=”Branch”>53</Field>
   <Field Name=”SearchableBranch”>2</Field>
   <Field Name=”ConsultantsDetails”>Lauren Jenner</Field>
   <Field Name=”Title”>BMW-318</Field>
   <Field Name=”Quantity”>1</Field>
   <Field Name=”ReservePrice”>17500.00</Field>
   <Field Name=”AuctionID”>10540</Field>
   <Field Name=”LotNo”>42</Field>
   <Field Name=”AuctioneerEstimateFrom”>15500.00</Field>
   <Field Name=”AuctioneerEstimateTo”>17500.00</Field>
   <Field Name=”VehicleType”>0</Field>
   <Field Name=”GoodTypeDescription”>Imported Car</Field>
   <Field Name=”IsFeaturedGood”>0</Field>
   <Field Name=”GoodStatusCode”>PASS</Field>
   <Field Name=”ShowOnInternet”>1</Field>
   <Field Name=”LotQty”>1</Field>
   <Field Name=”IsTradeItem”>0</Field>
   <Field Name=”CountryOfRegistration”>0</Field>
   <Field Name=”Year”>2001</Field>
   <Field Name=”Make”>392</Field>
   <Field Name=”Model”>154</Field>
   <Field Name=”Variant”>Ci</Field>
   <Field Name=”VehicleBody”>Coupe</Field>
   <Field Name=”Engine”>1890</Field>
   <Field Name=”Transmission”>Tipt</Field>
   <Field Name=”OdoReading”>51955</Field>
   <Field Name=”OdoType”>KMs</Field>
   <Field Name=”NumberOfOwners”>0</Field>
   <Field Name=”VehicleHistory”>Ex-Overseas</Field>
   <Field Name=”WOFExpiry”>2008-06-11T00:00:00.0000000+12:00</Field>
   <Field Name=”EngineType”>Petrol</Field>
   <Field Name=”Colour”>White</Field>
   <Field Name=”ConditionID”>$0 – $500 to spend</Field>
   <Field Name=”EngineNumber”>194E-559387</Field>
   <Field Name=”Chassis”>WBABL32010JR47649</Field>
   <Field Name=”VIN”>WBABL32010JR47649</Field>
   <Field Name=”DrawBeamCertificate”>0</Field>
   <Field Name=”RegFlag”>Un-Registered</Field>
   <Field Name=”RegistrationOverseasDate”>2001    </Field>
   <Field Name=”PreviousCountry”>Japan</Field>
   <Field Name=”ImportedAsDamaged”>0</Field>
   <Field Name=”CauseOfRegistration”>U</Field>
   <Field Name=”VehicleFeatures”>51,#Cassette Radio;#83,#Power Steering;#61,#Electric Windows;#49,#Central Locking;#31,#Anti-Skid Brakes;#37,#Alloy Wheels;#59,#Electric Mirrors;#75,#Airbags Multi;#48,#Certified Auction;#1,#Electronic Fuel Injection</Field>
   <Field Name=”VehicleCosts”>ENTRY,VNDR;TPP,BUYR;ENTRY,VNDR;ENTRY,VNDR;COMMISSION,VNDR;ENTRY,VNDR;ENTRY,VNDR;ENTRY,VNDR;ONROAD,BUYR</Field>
   <Field Name=”VehicleComments”>$350 additional costs for 6 months registration.  Odometer certified.;Certified vehicle  –  Free 6 month warranty, engine serviced, 105 point check</Field>
  </Method>

 I have a map that has a loopson vehicle node to create the <Method> element and a loop on each of the sub-elements of Vehicle to the <Field> element of the destination.  The Copy Text and Copy Name links are used to copy the data across.  This is working but I have hit a maximum:

The maximum number of possible data inputs to this node is 19.

This seems like a very low number; is there a way to increase this?  Is there another way?