Keep forms snapped together

I'm using some code I found on the net to make all forms in my application snap to each other's edges. This is working great, but I'd also like the forms to remain snapped together so that when I move one, all other forms snapped to it move with it, and any forms snapped to those forms move with those ones etc etc. I had a shot at it myself but I couldn't get much working... the form just gets stuck to the side of another form and I can't move it anymore.

This is the code I have so far:


procedure TMyForm.WindowPosChange(var Msg: TWMwindowposchanging);
var
    rWorkArea: TRect;
    StickAt : integer;
    wnd,parentwnd:HWND;
    sr:TRect;
    snapped:boolean;
    P:TPoint;
begin
    // =========================================================
    // SNAP TO OTHER FORMS
    stickat := 10;
    wnd := findwindowex(0,0,'TMyForm', nil);
    snapped:=false;
    parentwnd := 0;

    while(wnd <> 0) do begin

      if (wnd<>0) and (wnd<>self.Handle) and (GetWindowRect(wnd,sr)) then with Msg.WindowPos^ do begin
          //if we're within the snap stickatold then snap
          if (    (x <= (sr.right+stickat)) and
                (x >= (sr.right-stickat)) ) then begin
            if (((y > sr.top)or(y+height>sr.top)) and ((y < sr.bottom)or(y+height<sr.bottom))) then begin
                //disallow "open air" snaps
                snapped:=true;
                x := sr.right;
            end;
          end else if (((x + cx) >= (sr.left-stickat)) and
            ((x + cx) <= (sr.left+stickat))) then begin
            if (((y > sr.top)or(y+height > sr.top)) and (((y < sr.bottom)or(y+height < sr.bottom)))) then begin
                snapped:=true;
                x := sr.left-cx;
            end;
          end;

          if ( (y <= (sr.bottom+stickat)) and
            (y >= (sr.bottom-stickat)) ) then begin
            if (((x > sr.left)or(x+width > sr.left)) and ((x < sr.right)or(x+width < sr.right))) then begin
                snapped:=true;
                y := sr.bottom;
            end;
          end
          else if (((y + cy) <= (sr.top+stickat)) and
                ((y + cy) >= (sr.top-stickat))) then begin
            if (((x > sr.left)or(x+width > sr.left)) and ((x < sr.right)or(x+width < sr.right))) then begin
                snapped:=true;
                y := sr.top-cy;
            end;
          end;
      end;


      if snapped then break;

      // next window
      wnd := findwindowex(parentwnd, wnd, 'TMyForm', nil);

    end;
    // =========================================================
      
      
      
    // =========================================================
    /// KEEP FORMS SNAPPED TOGETHER
    wnd := findwindowex(0,0,'TMyForm', nil);
    snapped:=false;
    parentwnd := 0;

    while(wnd <> 0) do begin

      if (wnd<>0) and (wnd<>self.Handle) and (GetWindowRect(wnd,sr)) then begin
          // test to try and get the form to stay snapped to the right-hand side of another form
          if message.XPos = sr.Right then
            setwindowpos(wnd,0,sr.Left+message.XPos-left,sr.Top+message.YPos-top,0,0,SWP_NOZORDER or SWP_NOSIZE);
      end;


      if snapped then break;

      // next window
      wnd := findwindowex(parentwnd, wnd, 'TMyForm', nil);

    end;
    // =========================================================

end;


Any help appreciated :)