I don't believe any of the ML movements have been involved in a genocide nor approved a genocide. If you are referring to China not condemning Israel, well, you got me there.
Mao did not say to create a stock market. He said to collaborate with the national bourgeoisie. That's not communism. Under communism, there is no national bourgeoisie to collaborate with. Communism, as a state of existence, is classless.
So China has literally never been communist as a state of existence. China has been led by a communist party. That doesn't mean they have communism. It means they are building communism.
China is going through the capitalist mode of production. Just like every single industrial nation has done. We don't know of any other way to industrialize. One of the functions industrialization needs is the efficient allocation of resources. The stock market is a tool to make that happen. It's also a way to participate in and gather resource flows from imperialist countries in Chinese currency, which has important effects in anti-imperialism at the commanding heights of world economic systems.
You know how we know that China's industrialization process is run by communists and not capitalists? Because the industrial revolution impoverished millions in the West, but in China it lifted 800M out of abject poverty. China is a state with a communist party leading it through the capitalist mode of production to develop the productive forces of the economy. This is pretty straightforward stuff. It's only confusing if you're dogmatic about it and can't figure out why $EVIL_thing is present in a society that purports to be $GOOD_thing. Moral thinking will always confuse things. Abandon moral thinking, and it all makes much more sense