This Nemo is somewhere between his cinematic persona and the rehabilitated version common elsewhere. The episodes tend to take place in 1866, several years before the events of the film. Therein they can be taken as a kind of prequel. And in them, Nemo is definitely friendlier as an avenger of evil and righter of wrongs. He is still a fearsome avenger though.
The folks at the Nautilus Submarine Model site have been kind enough to scan several of these stories and later ones from the Walt Disney's Comic Digest (one should also note that Gold Key published the 20,000 Leagues Under the Sea movie comic in 1963 as well). Click on the cover below to visit their archive: