My PayPal email is not my login email - is that OK?

The email you use to login to the app does not have to be the same as your PayPal email. 

You enter your PayPal email when you request a payment. See this article for more info: https://support.survey.com/hc/en-us/articles/115003814566-Where-do-I-enter-my-PayPal-email-