Distance calculation short-circuited by typo

[xloem]

This line appears to have a critical typo in it: https://github.com/AeroScripts/HiddenEngrams/blob/bbcd4809160dd6ceeb3f67a59a0371c600f53bac/engram.py#L92 The last condition, or nodedown, will be True for all but the first index.

What's the intended behavior here?

I notice a similar check is replicated in the block below it.

Elsewhere it was tried to comment this out and replace the previous/next indices with whole object references to resolve the resulting sorting issues in example.py.