The vanguard Party after complete victory is achieved

Do you think a marxist-leninist world would see a change from parties or world party to left-communism style of dictatorship of the proletariat or do you think the change will be "world party -- communism" or what?

Some marxist-leninist think the vanguard party in each country or the world party can make the transition to full communism when the "technology and culture" are ready to support full communism.

I'm not sure I understand what you mean by "world party" communism. Nevertheless, what Marxist-Leninists are in unanimous agreement on is the necessity of a revolutionary vanguard organizing a political revolution which replaces the dictatorship of capital with one representing the interests of the proletariat. Beyond that end, the various sects which claim to descend from Lenin's writings (e.g., Trotskyists, Stalinists, and Maoists) disagree on everything from how the government should function to what communism entails.

As a syndicalist of a slightly Sorelian disposition, I believe that a type of vanguard will emerge during the formation of revolutionary syndicates—by which I mean, degrees of class consciousness are inevitably going to vary among workers. Consequently, those syndicates consisting of the most radical elements of the proletariat are going to be responsible for galvanizing the rest of the working class into direct action against the bourgeoisie. This, of course, diverges from traditional Leninism in that it rejects the notion of a political revolution and instead contends that capitalism can most effectively be dismantled via economic sabotage.

Regarding the notion of technology and culture having to be developed to a suitable extent in order to facilitate the transition into a communist mode of production, that is a historical materialist position I cannot find fault in.

Firstly, throw the notation of the entire world following a single ideology into the garbage bin. Even in a world mostly dominated by liberal capitalist economics, there are still plenty of remnant states resisting the system, whilst the states that do follow said ideology do so with different degrees of intensity. For example, France is closer to social democracy than to economic liberalism. And, it gets even more complicated when political systems are factored into it. I believe a world of "socialism" would still have as much conflict as our current state of affairs. The party-states of China and the Soviet Union competed against one another despite their ideologies only differing in intensity. Who's to say that the Marxist-Leninists would allow for mutualist revolutions and vice versa? There will be conflict between the different ideologies, whether through elections or war. The latter could either be cold or hot. I can't predict. In reality, this is merely the rule that has dominated history. There will always be this great competition between ideas to become the zeitgeist of their era.

Marxism-Leninism has shown by its history that it only leads to the vanguard party taking significant or complete control over the economy and society. They will not halt, and in fact they will only monopolize the party's power even further without the opposition of other ideological blocs. And, I see most of them as enemies standing in the way of the revolution nearly as much as fascists. This is not to say that I advocate for state repression of Marxist-Leninists, but instead I merely know where they and I stand when it comes to politics. As for the different tendencies, they differ merely in their intensity and occasionally in their support of an eventual communism.

Also, an economic system that only works in certain conditions is clearly one that is to be avoided. If you need Star Trek technology to be able to manage your economy, then you have failed in creating a decent economy.

As for the idea of the vanguard, I am fervently against it. I still believe in political revolution and economic revolution simultaneously, the strategy being according to time and circumstance. Personally, I would want a mass movement that has a mass political party, an industrial union, and a militia dedicated to self-defense and emergency last stands, but these are the parts of an American revolutionary movement. In other countries, the strategy will differ. Like the bourgeois liberal revolutions of the past, flexibility is essential, and each nation should decide on how their revolutionary transition from capitalism to socialism will play out. Basically, I will do what I think is needed to be done in America, while I support movements that at least roughly match with my ideals abroad with sacrificing their or my sovereignty.