I'm glad it helped. I will see what I can do (at least a hint in the description).

edit: Sadly I can't test dropS as it will traverse an infinite spine. Therefore I would have to test with a timeout. I'm not sure whether that's possible.

Things that I noticed:

• dropS: not working for negative numbers
• fibS: That's not how you should solve it (without lists please). (Hint: Think about a recursive definition of fibonacci numbers by using the stream itself.)
• primeS: I can't see what's the issue here, but again don't use lists please. Look up how a prime sieve algorithm works and implement it using streams. (It's very short, I promise and even bad ones should work.)
• Other that that it might also be related to codewars. Are you blocking JavaScript?