Thanks for the answer, Grant.

I have tried to tamper with Zorro.mt4 code

I've uncommented `Comment("Runs ",count," Loops ",loops); `

And seems like it's ever growing and never stops. So the problem was with the main loop.

I have made `uint loops = 0` non static and added loops limit in a single run ` while(cmd != 0 && loops < 500) `.

Now it works ok - MT4 is responsive and prices are updated.

But I'm still seeing Loops 1..2/Loops 500 blinking (a screencast is here https://drive.google.com/file/d/1XbQCqY3A8jYroq1Xq1p_2Dt3ljzZ8voW/view?usp=sharing)

So I assume Zorro sends too many unnecessary messages to the bridge.

Same problem with Z1 or TradeTest.

UPD: The code of the command which spams the channel cmd=170 (CMD_ASSET)