Pay Per View - Smoother Registration Process

Hi, I want to make a smoother registration/payment process for people who sign up.

For single payments, there is a button that says "click to confirm payment of $1" after returning from PayPal that the user must click to finally reveal the content. I'd like to "click" this for them with javascript to make a smoother experience. Are there any POST or GET values I can look for when they return from PayPal that lets me know I should trigger this click?

For subscriptions, I'd like to be able to have the user register, then immediately be redirected to PayPal, or at least back to the article they came from. I know it's possible to pass a simple ? to wp-login.php to achieve this. Where can I alter the URL that Pay Per View sends the user to?

Any other suggestions on how to approach these problems would be greatly appreciated.