I am sure this a stupid mistake on my part.... I create a DLL Test0.dll from the following
file (Test0.d):
=========
module Test0;

import std.stdio;

class Test0
{
export
 {
  int Test0( string ID0 )
    {
      printf("<Test0: ID={%s}> ",ID0.ptr);
      return ID0.length+5;
    }
 }  // export end
}

export Test0 instTest0() { return new Test0(); }
=========
Lib listing shows the following symbols:
Publics by name		module
_D5Test05Test05Test0MFAyaZi      _D5Test05Test05Test0MFAyaZi
_D5Test09instTest0FZC5Test05Test0 _D5Test09instTest0FZC5Test05Test0


Publics by module
_D5Test05Test05Test0MFAyaZi
	_D5Test05Test05Test0MFAyaZi

_D5Test09instTest0FZC5Test05Test0
	_D5Test09instTest0FZC5Test05Test0

=======
It seems everything exported properly.  I wrote the following Test Harness Test0h.d:
============
module Test0h;

import Test0;
import std.stdio;

int main()
{
	Test0 t0 = instTest0();

	puts("Starting main()");
	auto tret = t0.Test0("Harness Test0h");
	printf("T0 Ret=%d\n",tret);
	puts("Ending main()");
	return 0;
}
=========
with the following Import Definition file:
=========
module Test0;

import std.stdio;

class Test0
{
    int Test0(string ID0);
}

Test0 instTest0();
=========
Watching the compile in verbose mode I get the following with the concluding error:
==============
binary    I:\Progs\dmd2\windows\bin\dmd.exe
version   v2.050
config    I:\Progs\dmd2\windows\bin\sc.ini
parse     Test0h
importall Test0h
import    object	(I:\Progs\dmd2\windows\bin\..\..\src\druntime\import\object.di)
import    Test0	(Test0.di)
import    std.stdio	(I:\Progs\dmd2\windows\bin\..\..\src\phobos\std\stdio.d)
import    core.stdc.stdio	(I:\Progs\dmd2\windows\bin\..\..\src\druntime\import\core
\stdc\stdio.di)
..........
import    std.container	(I:\Progs\dmd2\windows\bin\..\..\src\phobos\std\container.d)
semantic  Test0h
semantic2 Test0h
semantic3 Test0h
code      Test0h
function  main
I:\Progs\dmd2\windows\bin\link.exe Test0h,,,"Test0.lib"+user32+kernel32/noi;
OPTLINK (R) for Win32  Release 8.00.8
Copyright (C) Digital Mars 1989-2010  All rights reserved.
http://www.digitalmars.com/ctg/optlink.html
Test0h.obj(Test0h)
 Error 42: Symbol Undefined _D5Test012__ModuleInfoZ

=========
I can't get the Test0 to be recognized.  If I add it to the compile then of course it works,
and runs properly, but that defeats the purpose of the DLL.  Can someone point out my error?

Found my own mistake:  In module Test0 the "import of std.stdio" caused the error.  There was nothing in the exports which required elements of std.stdio and somehow (don't know why) it caused ModuleInfo to be incomplete or omitted.