Very nice work! I've written a small API (https://m8.fyi/chord) to generate beautiful diagrams easily and quickly from Python. It's definitely not making a living from the income, but it is enough for a coffee every now and then.
Fixing the Paypal button issue will be more tricky! I just tried it in Firefox and it's fine, but I'm seeing temperamental issues in Safari. Will look into it further - thanks for the heads up.