While troubleshooting I realized that I'm often getting an access violation error in the MT4 EA log when enabling the Zorro EA on a chart. The smiley is then a sad one :-( and AutoTrading is disabled (although I ticked "Allow live trading" and "Allow DLL imports"). I can then enable AutoTrading via the button in the Standard toolbar, the smiley changes to :-) and everything looks fine. I did this a few times and like magic a can suddenly connect Zorro to both MT4 instances! Ok, question/problem 1) is fixed. Question 2 (the initial question of this thread) left open... Any comments?