multiatom attachment points and atom numbers

Consider this structure:

<?xml version="1.0"?>

<cml version="ChemAxon file format v5.10.0, generated by v5.11.5">

<MDocument>

  <MChemicalStruct>

    <molecule molID="m1">

      <atomArray atomID="a1 a2 a3 a4 a5 a6" elementType="C C Pd X P P" sgroupRef="sg1 sg1 0 0 0 0" x2="2.40625 2.40625 0.24062499403953552 2.40625 -1.2113009299968418 -1.2113009299968418" y2="2.117500066757202 0.5775000667572021 1.3956249952316284 1.3475000667572021 2.8475509192680057 -0.05630092880474913"/>

      <bondArray>

        <bond atomRefs2="a1 a2" order="2"/>

        <bond atomRefs2="a4 a3" convention="cxn:coord"/>

        <bond atomRefs2="a5 a3" convention="cxn:coord"/>

        <bond atomRefs2="a6 a3" convention="cxn:coord"/>

      </bondArray>

      <molecule id="sg1" role="MulticenterSgroup" molID="m2" atomRefs="a1 a2" center="a4"/>

    </molecule>

  </MChemicalStruct>

</MDocument>

</cml>

If I ask Marvin to show the atom numbers, it numbers them 1–6, even though there are only five atoms; it numbers the multiatom attachment point as atom number 4, even though it is not an atom.  This behavior needs to change.

Hi Bob,

This forum topic got lost somehow in our system as well, sorry about that.

I think I have to give a similar answer as inforum topic

I am suggesting that in the Marvin GUI, you omit showing the indices of the multicenters.  All of the other examples you cite represent individual atoms, even though the identity of those atoms may be indeterminate (as in R groups and list atoms) or fictional (as in pseudoatoms).  However, the multicenters are different, in that they add a *new* atom to the structure.  It is very confusing to students (and practicing organic chemists) to see a new "atom" with a new atom index where there should be none.  

If you perceive a need to be able to show the atom indices of multicenters, perhaps you can create an option to show them under View -> Misc -> Atom numbers.  But the default should be *not* to show them.