"So far it went good." - Sagt man das so im Englischen?
Nein. "So far it's going well".
ist das Deutsch korrekt? "bislang" + 'ging'?
In English, "good" is the adjective, "well" is the adverb.
"Till now it is going well" wasn't accepted. However, "Till now it went well" is a suggested answer, which I think sounds weird.
It sounds OK to me: "It went well until now," "Until now it has gone well," and so on. The German sentence is past tense--"ging," not "geht." The implication in English, at least, is that everything was going swimmingly, and then, wham!