http://libcom.org/forums/theory/why-all-kautsky-hate-29062011
It's been awhile since the Libcom thread above had posts, but CPGB comrade Ben Lewis has done some articles and translations on "when Kautsky was a Marxist" - proving the turn to renegacy in the mid 1910s and also criticizing left demonizations of Kautsky in earlier periods:
http://www.cpgb.org.uk/article.php?article_id=1004371 (Ben Lewis)
http://www.cpgb.org.uk/article.php?article_id=1004372
http://www.cpgb.org.uk/article.php?article_id=1004397 (Ben Lewis)
http://www.cpgb.org.uk/article.php?article_id=1004398
http://www.cpgb.org.uk/article.php?article_id=1004409
http://cpgb.org.uk/article.php?article_id=1004620 (Ben Lewis, recently)
Now, with regards to the heated exchange between the renegade Kautsky and Lenin, both the renegade and Luxemburg failed to mention two things when criticizing the Bolsheviks, instead mentioning the Cheka and the discredited Constituent Assembly, thus giving cover to parliamentary cretinism (sorry, but WSM partisans follow parliamentary cretinism):
1) Violation of equal suffrage (such that urban soviets had more electoral weight than rural soviets)
2) Anti-soviet Bolshevik coups d'etat in 1918, as documented by (the albeit rather conservative) historian Brovkin
http://www.revolutionaryhistory.co.uk/revs/front-lines.html
http://revleft.com/vb/bolshevik-coups-detat-t134819/index.html
Well, take a look at his 1922 Labour Revolution (the first chapter of which was dropped in translation, though it's a good critique of the Gorlitz program):
Where is the Kautsky hate against this major book? I don't see it. I would like to see it. With all the SPGB's preoccupation in bashing Lenin, they somehow failed to critique renegade Kautsky. It was the SPGB's responsibility. Even though the Fundamental Principles of Communist Production and Distribution by the Group of International Communists of Holland (GIK), is ambiguous toward Kautsky's book, they clearly thought it was a significant work.
Some other works by renegade Kautsky are listed at the bottom here.