help for disable automatically 1 line on bisschoff load-balancing

Hi all ,
I cofigured bisschoff load-balancing with 4 ADSL lines. it is working fine . but when 1 link (or more) becomes down from ISP to internet (not access to internet) , this line can’t disable automatically. i need disable automatically a line when it can’t access to internet .
Is there any solution ?
bisschoff load-balance is : http://mum.mikrotik.com/presentations/ZA13/bisschoff.pdf
Thanks for help .