Took a copy of 'TheCube.obj' and renamed it 'TheCube_7.obj', Imported that into PP2014 in a new scene with Andy deleted

External Name = TheCube_7 (Internal Name = TheCube_7)

Saved as 'TheCube_7.pp2'

{
version
    {
    number 10
    }
prop TheCube_7
    {
    geomCustom 
        { 
        ...
        } 
    }
prop TheCube_7
    {
    name    TheCube_7

New scene, deleted Andy, loaded TheCube_7.pp2 3 times

External Name = TheCube_1 (Internal Name = TheCube_7)
External Name = TheCube_2 (Internal Name = TheCube_8)
External Name = TheCube_3 (Internal Name = TheCube_9)

The 3Dcheapskate (also available in DAZ and HiveWire3D flavours) occasionally posts sensible stuff. Usually by accident.
And it usually uses Poser 11, with units set to inches. Except when it's using Poser 6 or PP2014, or when its units are set to PNU.

Forum: Poser - OFFICIAL

Subject: Why Does the External Name For A Prop SOMETIMES Have An '_1' Suffix