Errorlevel (windows)

Hi,

I'm scripting mtn in a batch file and I'm trying to get it to retry with different settings if it fails to generate a thumbnail. But the errorlevel doesn't change when it fails, the global variable ErrorLevel stays 0 even if it fails. Please add a return of anything other than 0 for the fail return, would be great option for further scripting and retrying failed files with alternate scripted settings.