Now that I'm at a keyboard I'd like to clarify a few things you don't seem to tunderstand:
Stalin considered himself a true communist, and when he came into power he purged the party of moderates who he felt were compromising on the mission. He considered his system communist or transitional to communism. European communists derided it as state capitalism, arguing that true communism (and socialism) cannot be definition exist when the means of production are owned by private individuals, whether a monopoly by an individual dictator who embodies the state, or by a group of investors under more conventional modes of capitalism. This is a subject of debate, but generally speaking western socialists and communists continue to hold the same view today, that the Soviet Union was never communist, while the Soviet Union and western capitalists agree with each other that it was/is. You can decide for yourself which group is applying which label for their own political convenience.
Marx didn't say any such thing. Capitalism is not a prerequisite, but the communist manifesto does argue that capitalism makes the developed world more vulnerable to a universal revolution:
"By creating the world market, big industry has already brought all the peoples of the Earth, and especially the civilized peoples, into such close relation with one another that none is independent of what happens to the others."
Marx did argue that a poor nation couldn't successfully start the revolution, for a few different reasons. One being that they wouldn't be able to provide the kind of quality of life that would tip the developed countries over, something he viewed as essential for spreading communism. European communists were always broadly skeptical about an attempted revolution in Russia, and by all accounts it turned out about as well as they'd expected.
I don't understand this question. Consult your dictionary, I guess? Capitalism and industrialization are different words and have different meanings. Industrialization is a mode of manufacturing. Capitalism is an ownership structure.
What question?
Non sequitur / answered above.