From Remove Nth Node from End of Linked List:

Bug: n < 0 leads to you removing the last node.

Your solution should have comments: I have NO idea how it works. And that's after reading it a couple times. If this was production code, I'd have wrapped it with unit-tests, thrown the implementation away and rewrote it.

How do I review honestly, without being overly harsh? I have a tendency to post an answer like that, and it's only after rolfl mentions it (@Pimgd - not a bit harsh, is it?) that I notice.