Sorry but like I said, you have all the info in my first post here if you want to take a look.
If you read my first post here you’ll see that I tried submitting a bug report from the support page and it failed, without giving any errors. I reported it here and gave full explanations so you have everything you need to fix it. It’s your software, I can’t be bothered any further I’m afraid.
I don’t know what to say, $response['body'] contained html source (i.e. <html><body> ...... The setup I have is with WP in a sub-folder, not in the root of the website but I’m not sure if that’s the cause.
Doing the change I suggested fixes the problem for me and the plugin then works fine.