QtObject Application Crashes When Running Scripts From TestComplete

We have application R ,   this script is written simply to launch it and detect initial UI objects:

function LaunchR() 
{
  Log.Message("In LaunchR");
  // if DP already is running, do not proceed 
  var p = NameMapping.Sys.WaitProcess("Register360", 0);
  if (p.Exists) {
    Log.Message("looks like Register360 is already running. Exiting...");
    return;
  }  
  
  // make sure Register360.exe exists
 if (!aqFile.Exists(TestedApps.Items("Register360").FullFileName)) {
    Log.Message("Register360.exe is not found at default TestedApps location...calling FindRegister360ExecutablePath...");
      
    TestedApps.Items("Register360").Path = FindRegister360ExecutablePath();
    // check it again
    if (!aqFile.Exists(TestedApps.Items("Register360").FullFileName))
        Runner.Halt("Cannot find Register360.exe!");
    }
    
  TestedApps.Register360.Run();
  aqUtils.Delay(3000);
  // get license dialog
 var licenseDlg = Aliases.Register360.WaitQtObject("QProgressDialog",-1,2000);
  while(licenseDlg.Exists)
  {
    Log.Message("Checking license dailog...");
    aqUtils.Delay(2000);
  }
  
 // unable to located license server page
 var licensedlg=Aliases.Register360.WaitQtObject("LicenseMgrConfigDlg",-1,2000);
 if(licensedlg.Exists)
 {
   Log.Warning("Unable to locate license server, check settings! ");
   Log.Picture(licensedlg.Picture(),'maybe a license problem');
   Runner.Stop();
 }
  
  // look for start page
  var ProjectSelector  = Aliases.Register360.WaitQtObject("ProjectSelectorWidgetRUBase",-1,2000);
  if (!ProjectSelector.Exists) 
  {
    Log.Picture( Sys.Desktop.Picture(), 'error pic' );
    Log.Error('Failed to find Project Selector');
  }
  aqUtils.Delay(5000);
  Log.Message("Out LaunchRegister360");
}

Currently it always crashes at line : 

// look for start page
  var ProjectSelector  = Aliases.Register360.WaitQtObject("ProjectSelectorWidgetRUBase",-1,2000);

In rare case, when it did not crash out application,  it cannot recognize this UI 'ProjectSelectorWidgetRUBase' , which is the following window:

Hope this is helpful

And in addition ,  manual test in the same way doesn't crash the application, so its not caused by our logic