mylb1=FindWindowEx(hMainWnd, 0, L"TMyListBox", L"");
   mylb2=FindWindowEx(hMainWnd, mylb1, L"TMyListBox", L"");

HWND GetActivePanel() {
   HWND hwnd=GetFocus();
   wchar_t buf[256];
   if (!GetClassName(hwnd, buf, TSIZE(buf)) || lstrcmp(buf, L"TMyListBox")) return 0;
   if (GetWindowText(hwnd, buf, TSIZE(buf)) || GetLastError()) return 0;
   return hwnd;
}

bool IsForbiddenLevelUp()
{
   char buf[1024];
   GetWindowText(stpath, buf, TSIZE(buf));
   if (*(int*)buf!='\\\0\\' || buf[2]=='\\')
…

bool IsForbiddenLevelUp()
{
   char buf[1024];
   GetWindowText(stpath, buf, TSIZE(buf));
   if (!((buf[0]=='\\' && buf[1]=='\\') || buf[2]=='\\'))
…

void DoMyAction()
{
   // focus to command line
   SendMessage(hMainWnd, WM_USER + 51, 4003, 0);
   // type of plugin
   SetWindowText(GetFocus(), "cd \\\\\\net");
   // ENTER-pressing
   keybd_event(VK_RETURN, 0, KEYEVENTF_EXTENDEDKEY, 0);
}

BOOL APIENTRY DllMain(HANDLE hModule,DWORD ul_reason_for_call,LPVOID lpReserved)

ul_reason_for_call==DLL_PROCESS_DETACH

DWORD __stdcall BackgroundSendData(void* Data) {
   auto_ptr<byte> ash((byte*)Data);
   SendMessage(hMainWnd, WM_COPYDATA, 0, (LPARAM)Data);
   return 0;
}

bool ChangeCurrentDir(const wchar_t* Path, bool NewTab) {
   int length=lstrlen(Path);
   auto_ptr<char> ash(new char[sizeof(COPYDATASTRUCT)+20+2*length]);
   COPYDATASTRUCT* cds=(COPYDATASTRUCT*)ash.get();
   char* data=ash.get()+sizeof(COPYDATASTRUCT);

   cds->dwData='DC';
   cds->lpData=data;
   char* p=data;
   if (Unicode) p+=wsprintfA(p, "\xEF\xBB\xBF");
   p+=WideCharToMultiByte(Unicode ? CP_UTF8 : CP_ACP, 0, Path, length, p, 2*length, 0, 0);
   p+=wsprintfA(p, "\r%cS%s", 0, NewTab ? "T" : "");
   cds->cbData=p-data+1;

   HANDLE thread=CreateThread(0, 0, &BackgroundSendData, ash.release(), 0, 0);
   if (!thread) return 0;

   CloseHandle(thread);
   return 1;
}

DWORD __stdcall BackgroundSendData(void* Data)
{
   SendMessage(hMainWnd, WM_COPYDATA, 0, (LPARAM) Data);
   return 0;
}

bool ChangeCurrentDir()
{
   COPYDATASTRUCT cds;
   char buffer[]="cd \\\\\\net";
   cds.dwData='DC';
   cds.lpData=&buffer;
   cds.cbData=sizeof(buffer);

   HANDLE thread=CreateThread(0, 0, &BackgroundSendData, &cds, 0, 0);
   if (!thread) return 0;

   CloseHandle(thread);
   return 1;
}

struct BackgroundSendDataData {
   COPYDATASTRUCT CopyData;
   char Raw[0];
};

DWORD __stdcall BackgroundSendData(void* Data) {
   BackgroundSendDataData* bsd=(BackgroundSendDataData*)Data;
   auto_ptr<char> ash((char*)Data);
   SendMessage(hMainWnd, WM_COPYDATA, 0, (LPARAM)&bsd->CopyData);
   return 0;
}

bool ChangeCurrentDir(const wchar_t* Path, bool NewTab) {
   int length=lstrlen(Path);
   auto_ptr<char> ash(new char[sizeof(BackgroundSendDataData)+20+2*length]);
   BackgroundSendDataData* bsd=(BackgroundSendDataData*)ash.get();

   bsd->CopyData.dwData='DC';
   bsd->CopyData.lpData=bsd->Raw;
   char* p=bsd->Raw;
   if (Unicode) p+=wsprintfA(p, "\xEF\xBB\xBF");
   p+=WideCharToMultiByte(Unicode ? CP_UTF8 : CP_ACP, 0, Path, length, p, 2*length, 0, 0);
   p+=wsprintfA(p, "\r%cS%s", 0, NewTab ? "T" : "");
   bsd->CopyData.cbData=p-bsd->Raw+1;

   HANDLE thread=CreateThread(0, 0, &BackgroundSendData, ash.get(), 0, 0);
   if (!thread) return 0;

   ash.release();
   CloseHandle(thread);
   return 1;
}

bool ChangeCurrentDir(const char* Path, bool NewTab) {
   int length=lstrlen(Path);
   auto_ptr<char> ash(new char[sizeof(BackgroundSendDataData)+20+length]);
   BackgroundSendDataData* bsd=(BackgroundSendDataData*)ash.get();

   bsd->CopyData.dwData='DC';
   bsd->CopyData.lpData=bsd->Raw;
   char* p=bsd->Raw;
   p+=wsprintf(p, "%s\r%cS%s", Path, length, 0, NewTab ? "T" : "");
   bsd->CopyData.cbData=p-bsd->Raw+1;

   HANDLE thread=CreateThread(0, 0, &BackgroundSendData, ash.get(), 0, 0);
   if (!thread) return 0;

   ash.release();
   CloseHandle(thread);
   return 1;
}

cd "путь\путь" не путь 
cd путь\п у т ь\путь путь     

<first_path>\r<second_path>\0<flags>

static char cdnet[]="\\\\\\net\r\0S";

DWORD __stdcall ExecEmulate(void)
{
   // focus to command line
   SendMessage(hMainWnd, WM_USER + 51, 4003, 0);
   // ENTER-pressing
   keybd_event(VK_RETURN, 0, KEYEVENTF_EXTENDEDKEY, 0);
   return 0;
}

bool ExecCommandLine()
{
   HANDLE thread=CreateThread(0, 0, ExecEmulate, 0, 0, 0);
   if (!thread) return 0;
   CloseHandle(thread);
   return 1;
}

LRESULT CALLBACK CallMouseHookProc(int nCode, WPARAM wParam, LPARAM lParam)
{
   if (wParam==WM_LBUTTONDBLCLK)
   {
      HWND mylb=GetActivePanel();
      POINT pt;
      GetCursorPos(&pt);
      ScreenToClient(mylb, &pt);
      int index=SendMessage(mylb, LB_ITEMFROMPOINT, 0, MAKELPARAM(pt.x, pt.y)); // get item index under cursor
      if (!index&&IsForbiddenLevelUp())
      { // it is ".." item and we should refuse 'level up'
         HWND cmdpanel, edit;
         if ((cmdpanel=FindWindowEx(hMainWnd, cmdpanel, "TMyPanel", "")))
            if ((edit=FindWindowEx(cmdpanel, edit, "TMyComboBox", "")))
               if ((FindWindowEx(edit, 0, "TMyComboBox", "")))
               {
                  char buf[1024];
                  int k=GetWindowText(edit, buf, TSIZE(buf));
                  
pseudo code: if buf not emty then
                     ExecCommandLine();

                  
                  return 1; // kill doubleclick event
               }


         DoMyAction();
         return 1; // kill doubleclick event
      }
   }
   return CallNextHookEx(hMouseHook, nCode, wParam, lParam);
}

copy c:\temp\a.txt d:\temp2\b.txt

cd \\192.168.1.2

   while (1) {
      if (!(cmdpanel=FindWindowEx(hMainWnd, cmdpanel, "TMyPanel", L""))) break;
      if ((cmdlbox=FindWindowEx(cmdpanel, 0, "TMyComboBox", L"")) || (cmdlbox=FindWindowEx(cmdpanel, 0, "TComboBox", L""))) {
         HWND pathpanel=FindWindowEx(cmdpanel, 0, "TMyPanel", 0);
         int k=GetWindowText(pathpanel, buf, TSIZE(buf));
         if (k&&buf[k-1]=='>') {
            stpath=pathpanel;
            cmdline=FindWindowEx(cmdlbox, 0, "Edit", 0);
            break;
         }
      }
   }