Seems like no one else is having this problem.

I finally got a response from Support. I guess I'll try creating a new account as this problem happens with all pics I upload.
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Hello,
Our QA staff just got back to us on this issue.
"We don't know what happened. The colors definitely got shifted a bit from the original to the thumbnail. This seems to happen a bit in general, but it’s very noticeable in this case. This process is out of our hands"
Sorry about this miscolor issue.
Thank you,
Auctiva support
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