When the about:blank is about to happen, ZP didn't stay in that Goto action for even 1/100 of a second. It displays about:blank immediately. Even if we assume there is a temporary problem with the proxy, shouldn't ZP at least try to see if there is a time out?
This about:blank problem occurs randomly. When it happens, it's acting as if there is no Goto Action.
It skips Goto action immediately as if it doesn't exist, and gives about:blank and jumps to the next action. It doesn't appear to be trying the proxy.