Hello Honour

1. How do I get it to automatically set the user to 'allowed' upon registering. Everyone who signs up can have access.   I don't want them to be set the default - 'blocked'.

I do not understand clearly what you mean here. What should be allowed?
a) The user to the system in general or 
b) should the user be allowed to edit and save certain content types?

2.  How do I set the field to 'required'?

When you are in SEBLOD content type User in Admin Form or Site Form Tab, on the right hand side there are option buttons 1-6.
Click on number 3 "Required & Validation".
Then click on the blue link "Optional" next to the field that you wnat to set to required. In the Popup you can adjust the settings for required and also for validation rules.