This is actually a great spider tool, I like it.
I have found the cause, but it was only a cosmetic issue, no worries. The reason was that in the invisible results area there as the link for the “Show more results” and it had the default value of “?s=” without the search phrase parameter. Since it's invisible, search engine don't account for it. I removed that default value from the code, now it should not appear in the spider anymore.
I will look into that statistics bug as well later, because I'm planning to re-work that section anyways in a future release.Best,
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