Indeed, the German Nazbols were never on good terms with the Nazis. The left wing of the NSDAP (brothers Strasser, the early Goebbels, Ernst Röhm) mustn't be confused with the national bolshevik movement which mainly emerged from the writings of former KPD members Heinrich Laufenberg and Fritz Wolffheim. They propagated "volk struggle/people's struggle" instead of class struggle because they believed that not only the working class but the whole people is revolutionary and that nationalism and socialism are inseperable.
Their ideas were adopted by people like Ernst Niekisch and Karl Otto Paetel.
Niekisch, although being member of the USPD and involved in the Bavarian Soviet Republic, was more "right-wing"; he rejects class struggle and thus Marxism as "exaggeration of the importance of class struggle [...] which leads to a radical overthrow of traditions". Here he mainly refers to Prussian traditions which he idolized and seeked to combine with the "benefits of socialist economy and society" (= "Prussian socialism"). He emphasizes that the German people have to rise up against Versailles and form a strong state based on nationalism, Prussian militarism and authoritarianism and socialist economy. Then this new Germany has to ally with the USSR against the "rotten West" which is decadent and dying (he e.g. thought that the blacks ruin France). Niekisch was the editor of the "national revolutionary" newspaper
Widerstand (Resistance) and in 1932 he wrote the book "Hitler. Ein deutsches Verhängnis" (Hitler. A German doom, here is the
cover) and warned about the Nazis rise to power. This got him imprisonment and torture under the Nazis. Later he first lived in the DDR but then moved to West Berlin.
Karl Otto Paetel on the other hand was more "left-wing" and upheld class struggle and seeked close relations with the KPD but he still was strictly anti-democratic and nationalist. He founded the "Gruppe Sozialrevolutionärer Nationalisten" (Group of Social Revolutionary Nationalists). He also massively criticised the Nazis and published his main work, "The National Bolshevist Manifesto" in 1933. After imprisonment he fled to Paris in 1935 where he published "national revolutionary materials" for his comrades in Germany and tried to invade and undermine the Hitler Youth (which led to the founding of the "Black HJ", a group of oppositional HJ members). In 1965 he published a book about the history of the German national bolshevist movement (
cover).
Although this was not intended Niekisch and to a certain degree Paetel, too influenced the "left" Nazis, like the brothers Strasser. They later left the NSDAP and created the "Black Front" which adopted the "Hammer and Sword" symbolism introduced by Niekisch (
Strasserist flag and
Niekisch's symbol). But as I said, the "National Bolsheviks" and the "Strasserists" had different aims and followed different ideas and while both clashed with the Nazis the National Bolsheviks never supported the NSDAP while the Strasserists only left the party when they saw that they had no chance against Hitler.
While the Natonal Bolsheviks were indeed pro-USSR and had sympathies for certain aspects of socialism they were clearly nationalist, volkish, anti-democratic and often racist. Today there are "autonomous nationalists" in Germany who use some of Niekisch's slogans in order to attract a "national revolutionary" audience and there is also a very small group of German Nazbols who mainly uphold Niekisch (some are pro-Strasser, some pro-Paetel) and try to put the works of the original Nazbols online and "invade" leftist and Antifa demonstrations with Niekisch's slogans for national revoltuion. While they are anti-NPD (German neo-nazi party) they clearly show fascist tendencies and are usually very unwelcome at leftist demonstartions. Ustrialov is a different story again and Russia's Nazbols are indeed very different from the Nazbols of the Weimar Republic.