Problems with Picking using D3DXIntersect()

Hi all, I'm currently having trouble getting picking to work in my Bezier curve application. The idea is to have a sphere at each of the control points along the bezier curve and I can then click on a sphere to move its respective control point. All the bezier math etc. is fine but I can't get picking to work. I'm using the DirectX August 2007 SDK and C++. First of all each control point is defined:

struct CtrlPoint							//A structure to hold data on a control point
{
	D3DXVECTOR3 position;	//Position of the control Point
	ID3DXMesh* mesh;		//A mesh which will represent the control point visually
	float radius;			//Radius of the sphere (of the mesh which represents the control point)
	bool selected;			//Whether the point has been selected by the mouse
	D3DXMATRIX world;		//The control point's world matrix (for calculating picking)
}ctrlPoint[NUMCTRLPOINTS];	//Creates an array of control points

Then the sphere displayed at the point is created thus:

D3DXCreateSphere(gd3dDevice,
		 ctrlPoint.radius,
		 20,
		 20,
		 &ctrlPoint.mesh,
		 0);

and displayed:

D3DXMatrixIdentity(&I);
//Display a sphere each control point
for(int i=0; i<NUMCTRLPOINTS; i++)	//for each control point
{
	D3DXMATRIX T;
	//Translate the matrix to the position of the control point
	D3DXMatrixTranslation(&T, ctrlPoint.position.x, ctrlPoint.position.y, ctrlPoint.position.z);
	//Calculate the total movement/rotation into one matrix
	S = I * T;
	//Transform to the position/orientation of the matrix
	gd3dDevice->SetTransform(D3DTS_WORLD, &S);
	//Store the control point's world matrix
	gd3dDevice->GetTransform(D3DTS_WORLD, &ctrlPoint.world);
	//Set the standard red material for the control point
	gd3dDevice->SetMaterial(&Material::RED_MTRL);
	//Draw the Sphere
	ctrlPoint.mesh->DrawSubset(0);
}

As you can see I translate to the position of each point Set the world matrix and store it then draw the point. Don't think there's any problem there. Then in my main loop I make a call to the pick function which takes in all the necessary paramaters:

//If the left Mouse Button is clicked and wasn't down last frame
if(gDInput->mouseButtonDown(0) && mouseClicked==0)
{
	POINT cursorPos;
	//Get the position of the cursor
	GetCursorPos(&cursorPos);
	//Make it relative to the client area window
	ScreenToClient(*mainWnd, &cursorPos);

	D3DVIEWPORT9 vp;
	//Get the current viewport
	gd3dDevice->GetViewport(&vp);

	D3DXMATRIX proj;
	//Get the current Projection matrix
	gd3dDevice->GetTransform(D3DTS_PROJECTION, &proj);

	D3DXMATRIX view;
	//Get the current view matrix from the camera class
	camera->getViewMatrix(&view);
	//gd3dDevice->GetTransform(D3DTS_VIEW, &view); //Not using this method to get view matrix currently

	//Calculate Picking
	pick->doPick(cursorPos, vp, proj, view,
                     bezier[0]->getCtrlPoints(), //Array of control point structs
                     bezier[0]->getNumCtrlPoints() //Number of control Points
                     );
}

The view matrix is currently calculated in the camera class (taken from Frank D Luna's DirectX book) and works fine for rotation/translation of the camera etc. As you can see there is a line commented out which gets the view matrix using 'gd3dDevice->GetTransform()' this method gives different results (still doesn't work) when doing the picking calculations even though it should essentially return the camera view matrix anyway as it is updated each frame:

//Update the view matrix representing the cameras new position/orientation.
D3DXMATRIX V;
camera->getViewMatrix(&V);
gd3dDevice->SetTransform(D3DTS_VIEW, &V);

However there must be a problem in my picking function anyway as it still doesn't work no matter which way I get the view matrix. Here's the picking function which is mostly taken from the Toymaker Picking Tutorial

void Pick::doPick(POINT cursorPos, D3DVIEWPORT9 vp, D3DXMATRIX proj, D3DXMATRIX view, Bezier::CtrlPoint* ctrlPoint1,Bezier::CtrlPoint* ctrlPoint2, int numCtrlPoints)
{
	for(int i=0; i<numCtrlPoints; i++)	//for each control point
	{
		D3DXVECTOR3 v;
		v.x = ( ( (2.0f * cursorPos.x) / vp.Width) - 1 ) / proj._11;
		v.y =-( ( (2.0f * cursorPos.y) / vp.Height) - 1 ) / proj._22;
		v.z = 1.0f;

		D3DXMATRIX m;
		D3DXVECTOR3 rayOrigin,rayDir;

		D3DXMatrixInverse( &m, NULL, &view );

		// Transform the screen space pick ray into 3D space
		ray.direction.x = v.x*m._11 + v.y*m._21 + v.z*m._31;
		ray.direction.y = v.x*m._12 + v.y*m._22 + v.z*m._32;
		ray.direction.z = v.x*m._13 + v.y*m._23 + v.z*m._33;
		ray.origin.x = m._41;
		ray.origin.y = m._42;
		ray.origin.z = m._43;

		// Use inverse of matrix
		D3DXMATRIX matInverse;
		D3DXMatrixInverse(&matInverse,NULL,&ctrlPoint1.world); //Use the world matrix stored for each control point

		// Transform ray origin and direction by inv matrix
		D3DXVECTOR3 rayObjOrigin,rayObjDirection;

		D3DXVec3TransformCoord(&rayObjOrigin,&ray.origin,&matInverse);
		D3DXVec3TransformNormal(&rayObjDirection,&ray.direction,&matInverse);
		D3DXVec3Normalize(&rayObjDirection,&rayObjDirection);

                //Check for an intersection between ray and control point mesh
		BOOL hit=0;
		D3DXIntersect(
			ctrlPoint1.mesh,
			&rayObjOrigin,
			&rayObjDirection,
			&hit, NULL, NULL, NULL, NULL, NULL, NULL);

		if(hit==1) //If there is a hit
		{
                        //Display the point we hit and the screen position which was clicked on
			char buffer[256];
			sprintf(buffer,"Point %d: X-%ld, Y-%ld\n", i, cursorPos.x, cursorPos.y);
			::MessageBox(0, buffer, 0, 0);
			ctrlPoint.selected=true; //Set the control point to have been selected
		}
	} 
}

Now the problem I currently have is that I can click anywhere on the screen (even not over any control point) and it will always register me as having clicked on all the control points. When I click over a control point it still registers a hit on all of them. Using the second method of getting the view matrix I mentioned earlier does the exact opposite. It never registers a hit at all. I have no idea where I'm going wrong as I have followed numerous tutorials always having the same outcome, either always registering a hit or never registering one. I guess this is going to be a bit of a mammoth post but hopefully someone can suggest possible reasons for what's happening. Thanks! Here's a screenshot of my App to give you a better understanding of what it looks like, theres a curve, a number of red spheres representing the control points and an object following the curve.

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