If you can't show us the code, consider working on reducing the code you have until it consists of little more than

use Win32::GUI;

# create main window
# connect MouseUp handler to events of the window

$main->Show();
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Most likely while reducing your program to this minimal example, you will find where the error lies.

If you can't even do that, we cannot help you either.

I am not getting anywhere so here is some code

 
use Win::GUI;
$main = Win32::GUI::Window->(-name=>'Main',-width=>600,-heigth= >600);
$Screen = new Win32::GUI::DCC("DISPLAY");
$main->Show;
Win32::GUI::Dialog();

sub Main_Terminate{-1;};
sub Main_MouseDown{
($x,$y)=Win32::GUI::GetCursorPos;
print "$x\n";
print "$y\n";
}
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Help would be appreciated, i have everything ready to.