WARNING: Error storing memory pool transaction c0c958698d61b260a885115a7e2ccec1a25c8a121c0da9ec6165f0ce11920c9b: Spent input not found
Nope it looks fine. Those errors aren't a problem. Example: memory pool isn't full yet and there's txs depending on other txs in the mempool that aren't yours. It's normal. I'll make the wording sound less extreme.
Important is that you're able to run 'sx fetch-last-height' and the block height matches blockchain.info or somewhere else.
I need to document these tools better. Sorry about that. I'll be making efforts towards that goal as documentation is important.