If I study a word on one list then start another and it has that word in common does Skritter take that into account and not test me on it until it’s due from before?
Exactly what you describe! Having the same word in multiple lists will not affect scheduling, it does take that into account.
I can finally log in again. I’m glad to hear that. I was having a little dilemma over starting a kanji list that’s already on the site versus making my own from Kanji in Context so this really helps.