This is mad!

This is not correct. Consider the case:

Kata.countSmileys(Vector(":)",":",")")) // actual: 2, expected: 1

You could use normal recursion instead of the tail recursion, that way you wouldn't need the extra argument.
But this works nice anyways ;)

The rounding corresponds to how the language works.

This is will fail for cases where the sum of digits are equal.

Fixed

Fixed -> Object.freeze(Math); Object.freeze(Math.random);

What do you mean?

Fixed

Fixed

Fixed

Fixed

Fixed

Fixed

I didn't know about succ :( Well done