Slow work

Hello. Can someone explain me why my templates often stop and I see this for more than 5 mins in some threads. The page is fully loaded and everything is ready for the next step, but zennoposter just staying and not doing anything . There no such huge delay when I run the templates in project maker. It is not a big problem but its really annoying when I run 5 threads and 3 of them just waiting for something . It is not a hardware resource problem because there is more than enough for much more threads ...

Thank you