Message mapping 2D structure

Question

Please excuse me, this seems to be a very simple issue but being resonably new to message mapping I am having issues solving it.
Ok each field maps to a repeating structure in the target IDOC, I ahve duplicated the subtree in the Structure and mapped each of the fields.
_Source_                    _Desired_                                      _Actual_
<header>                    <header>                                          <header>           
  <line1>                     <line1>                                           <line1>
     <Field1>                    <Field1>                                           <Field1>
     <Field2>     Message        <Field2>                                           <Field2>
     <Field3>       Mapping       <Field3>                                          <Field3>
   <line2>           ------>   <line2>                                               <Field4>
     <Field4>                      <Field4>                                         <Field5>
     <Field5>                      <Field5>                                         <Field6>   
     <Field6>                      <Field6>                                     <line2>
Each lineNode has been mapped across, and the FieldNode's have been mapped to the line as well. I have had to map the lineNode to the fieldNode as well as I am duplicating the subtree for the fieldNode which is 1..N range.
My issue is all the fields are mapping into the first node and not maintaining their structure. The value in the fields is coming through correctly in the repeating structure but the node itself is misplaced.

Answer 1

Thought it was solved ... it isnt...
To clafiry...
There are fields in the incoming structure that map into Nodes in the target structure ...
So Field1 in Line1 .... will actually become Field1Node in the target. To add addition complexity the target node is a repeating node, so used the copt subtree feature but I think it is loosing context.
So...
<lineNode1>    -
> <lineNode1>
    <field1>      -
>     <FieldNode1>
                                                           <field1 value>
                                                           <field1 constant> --- provided by PI
    <field2>     -
>    <FieldNode2>
and so on .... basically the fields in the originating message and creating a bunch of nodes in the user exit, With some small constants to hardcoded in PI to add context to the value in the field.
A real example ...
<saleLine1>                                             <saleLine1>
<saleValue>100</saleValue>                                 <userExitGenericNode>
</saleLine1>                                                    <Value>100</Value>
                                                                 <ID>SaleValue</ID>
                                                            </userExitGenericNode>
                                                        </saleLine1>