Hello there!
Sorry for the trouble you had with this insertion :)
I didn't intend to "rip off" you or other developers. Essentially, this is the first insertion I have added in 2017 on itch.io and, at the time, I hadn't enough knowledge about the platform. Honestly, I didn't edited anything about this specific one as it's not a popular plugin and I never found a moment for checking into.
Moreover, I'm not an english native speaker. At the time, my language skills were worse than now.
When I will have some time, I will do a complete rewriting for the page and an update to the plugin. For now, I have removed the "Suggest an alternate default price" tick and applied the correction on the line related to needed images.
Thank you for reporting the issue :D