@paudet You can try this script to take screenshots of the opened application
import com.kms.katalon.core.windows.driver.WindowsDriverFactory
import com.kms.katalon.core.windows.keyword.helper.WindowsActionHelper
String screenshotLocation = 'Put the screenshot location here'
WindowsActionHelper.create(WindowsDriverFactory.getWindowsSession()).takeScreenshot(screenshotLocation)