64-bit code calls 32-bit DLL through ATL COM adapter but gets 64-bit version, not 32-bit

// Client2.cpp				2009-08-06
//
//		Test driver for COM Adapter3 to access the Calculator DLL
//
#include <windows.h>
#include <objbase.h>
#include <iostream>
#include <iomanip>
using namespace std;
 
#include <atlbase.h>
#include <atldef.h>
#include <windef.h>
#include "ComAdapter3_i.h"
 
///////////////////////////// Interface code for accessing the COM Adapter ///////////////////////////////////////
 
int main()
{
	// Initialize COM
 
	HRESULT hr = 0;
	LPUNKNOWN pServer = 0;
	ICoCalc* calc = 0;
 
	::CoInitialize(NULL);
 
// Tried this:
	//PVOID sv = 0;
	//Wow64DisableWow64FsRedirection(&sv);
 
	hr = CoCreateInstance(CLSID_CoCalc, NULL, CLSCTX_LOCAL_SERVER, IID_IUnknown, (LPVOID*) &pServer);
	if (FAILED(hr))
	{
		cout << "Failed to load server\n";
		goto cleanup;
	}
 
	hr = pServer->QueryInterface(IID_ICoCalc, (LPVOID*)&calc);
	if (FAILED(hr))
	{
		cout << "ICalc not found" << endl;
		goto cleanup;
	}
 
	////////////////////////// Normal Application Code //////////////////////////////
 
	cout << "\n\tCalcTest\n\n\n";
 
	long a = 0, b = 0, c = 0;
 
	while (cout << "Enter two integers or Q to quit: ", cin >> a >> b)
	{
		// COM keeps the function addresses in the VTable, makes virtual function calls
		c = calc->Add(a, b);		// a proxy layer could hide calc pointer
		cout << "Sum = " << c << endl;
///  I modified Add to just:   return 8 * sizeof(size_t);
///  It returns 32 or 64 to show what version of code is running in the "COM server"
		cout << "\nClient calc: " << calc << endl;
		cout << "Add: a: " << a << "  &a: " << &a << endl;
		cout << "     b: " << b << "  &b: " << &b << endl;
		cout << "     c: " << c << "  &c: " << &c <<endl;
	}
 
cleanup:		// Cannot build a new ComServer until its usage count is zero.
	if (calc) 
		hr = calc->Release();
	if (pServer)
		hr = pServer->Release();
	CoUninitialize();
	return hr;
}
 
 
 
// CoCalc.cpp : Implementation of CCoCalc
//
//	Test program with local Add function representing code that would be in 32-bit DLL.
//	Calling the DLL will be easy after the 64-32 barrier is fixed.
//
//  When launching Visual Studio, run as Administrator so that various build steps will work.
//  Build ComAdapter3. Then build ComAdapter3PS by right-clicking on that Project name and selecting
//  Project only > Rebuild on ComAdapter3PS.
//
//  Next, go to Client3 directory and run COPY.BAT from a command line window. It copies some generated files.
//  I like keeping the client and server separated.
//  Then build the client3 program and run it.
//  Be careful to check that client is 64-bits and Adapter is 32-bits. Test shows 64-bit Adapter is loaded, matching the
//  bit-ness of the client. I need to turn off the direct matching and access the 32-bit version.
//  The code is basically correct, just missing the magic instructions to override that mapping.
//  Building both Client and Adapter in 32 or 64-bit mode shows correct 32 or 64 output.
 
#include "stdafx.h"
#include "CoCalc.h"
#include <cstddef>
#include <cstdlib>
 
// CCoCalc
 
STDMETHODIMP CCoCalc::Add(LONG a, LONG b)
{
	long c = a + b;
 
	c = sizeof(size_t) * 8;		// report 32-bit or 64-bit version instead of sum to prove the 64 to 32 call works
 
	return c;
}