Godard's movie implicitly attacks the political impotence, naiveté, party élitism and bourgeois romanticism of European Maoists, who focuse too much on the "form" of Capitalism, whilst neglecting analyses on the content of Commodity production: its political economy dynamics.
What to do for the making of a Participatory Front and How to do that
Whomever wanna read my Postcapitalist Manifesto might conveniently click here!
• Whomever doesn't give a fig about this song and wanna watch a cartoon may conveniently watch Karl Marx Vs Captain Capitalism
• Whomever wants to read about my stance on the Occupy Wall Street movement may conveniently read my article the political character of the Occupy Wall Street Movement
Whether Godard was supportive or not of Maoism in general (notice that, however, I specified French Marxism and "European" Maoism), it is not very relevant to the dialectica question. In fact, one might argue - not without reason - that the most historically productive interpretation of an artwork (I explain what it is in my paper "The Problems of Democratic Centralism and their Solutions) can potentially be antithetical to the interpretation intended by an author (in our case Godard).
Coming back to the movie in question, when the "revolutionary" girl e.g. is heavily criticised for her tactical naivety in the train, also bourgeois Leninist/Maoist groups of the likes of Rote Armee Fraktion (RAF) and Brigate Rosse (BR) receive a perceptive attack, straight to their raison d'etre. Similarly, "cultural" Marxism, which was a common trend in the French XX century reality, far from serious economic investigation - is perpetually (unintentionally or not) ridiculed throughout the movie, especially for its verbosity and bourgeois character.
Ultimately, the interpretation that matters is that which gets us closer to a dialectical change and not necessarily the interpretation wanted by an author (though Godard appears to be intelligently critical of the European leftist scenario)
For more information on the dialectical concept of interpretation, dialectical morality etcetera check my work "The Problems of Democratic Centralism and Their Solutions".