Problems using ControlClick method in VBScript

[GTAVLover 0]

I recently tried to use ControlClick method to send a mouse click command to a button in a application, but I noticed that it is not working when I give first parameter as a window handle (HWND). But, when I give class name or window title, it works fine. I used AutoItX3 and VBScript. 

Following are the commands I tried in VBScript:

Dim WINAPI: Set WINAPI = WScript.CreateObject("WinAPIWrapper.WINAPI")
Dim AutoItX3: Set AutoItX3 = WScript.CreateObject("AutoItX3.Control")

Dim WindowHandle: WindowHandle = WINAPI.WinAPI_FindWindow("my window title", "my window class") 'Window handle obtains fine by my wrapper function

'Above window handle is obtained as a hexadecimal string. (I.E. - 0x00000000)

I tried it like:

WScript.Echo CStr(AutoItX3.ControlClick(WindowHandle, "", "[CLASS:Button; INSTANCE:1]")) // DOES NOT WORK
WScript.Echo CStr(AutoItX3.ControlClick(CLng("&h" + Replace(WindowHandle, "0x", "")), "", "[CLASS:Button; INSTANCE:1]")) // DOES NOT WORK
WScript.Echo CStr(AutoItX3.ControlClick(000000, "", "[CLASS:Button; INSTANCE:1]")) // DOES NOT WORK
WScript.Echo CStr(AutoItX3.ControlClick(0x00000000, "", "[CLASS:Button; INSTANCE:1]")) // DOES NOT WORK

Only following commands work:

WScript.Echo CStr(AutoItX3.ControlClick("[CLASS:my window class]", "", "[CLASS:Button; INSTANCE:1]")) // WORKS FINE
WScript.Echo CStr(AutoItX3.ControlClick("My window title", "", "[CLASS:Button; INSTANCE:1]")) // WORKS FINE

 

If any of your suggestions don't work, I will have to write a wrapper function myself to send mouse click commands. I chosen AutoIt V3 because it is good specially when comes to send keystrokes to applications. Please tell me why this won't work when I give window handle as first parameter.

Thanks in advance.

Edited August 1 by GTAVLover