Почти как в видео.
#define #MK_LBUTTON:     0x0001
#define #WM_MOUSEMOVE:   0x0200
#define #WM_LBUTTONDOWN: 0x0201
#define #WM_LBUTTONUP:   0x0202
$arr_hwnd[0] = HGET(INT($_xmax * 0.25), INT($_ymax * 0.5)) 
$arr_hwnd[1] = HGET(INT($_xmax * 0.75), INT($_ymax * 0.5))
WNDGETINFO($arr_hwnd[0], $left, $top, $width, $height)
SETTHREAD(TH_DUP_MOUSE, 1)
   
WHILE(#TRUE)
   IF(ISKEYDOWN(1) = 1)
      $K = 1
      WHILE(ISKEYDOWN(1) = 1)
          WAITMS(1)
      END_CYC
      $K = 2
      WHILE($K = 2)
         WAITMS(1)  
      END_CYC
   END_IF
END_CYC
THREAD(TH_DUP_MOUSE, 0)
   $x = $_xmouse - $left
   $y = $_ymouse - $top
   SWITCH($K)
   CASE(0)
      SENDMESSAGE($arr_hwnd[1], #WM_MOUSEMOVE,   #NULL,       $x + ($y * 65536))
   CASE(1)
      SENDMESSAGE($arr_hwnd[1], #WM_LBUTTONDOWN, #MK_LBUTTON, $x + ($y * 65536))
   CASE(2)
      SENDMESSAGE($arr_hwnd[1], #WM_LBUTTONUP,   #MK_LBUTTON, $x + ($y * 65536))
      $K = 0
   END_SWITCH
   WAITMS(5)
END_THREAD
Если бы я не видел кода из видео, то я бы сделал примерно так. 
$arr_hwnd[0] = HGET(INT($_xmax * 0.25), INT($_ymax * 0.5))
$arr_hwnd[1] = HGET(INT($_xmax * 0.75), INT($_ymax * 0.5))
WNDGETINFO($arr_hwnd[0], $left, $top, $width, $height)
STRSEPARATE("0:0x0200:0x0000:1:0x0201:0x0001:0:0x0202:0x0001:1:0x0200:0x0000", ":", $arr_state)
WHILE(#TRUE)
   $i = $state * 6 + ISKEYDOWN(1) * 3
   $state = $arr_state[$i]
   SENDMESSAGE($arr_hwnd[1], $arr_state[$i + 1], $arr_state[$i + 2], ($_xmouse - $left) + (($_ymouse - $top) * 65536))
END_CYC