Where can I find tech docs?

Hi, I think your plugin is well done and I’d like to use it. Probably a premium version. Though, I’m a developer. So I want to use some code. Where can I find tech documentation?

For example, I want to

– find out and use any js (I see you use ajax by default) or php hook to customize what happens after a user has registered or after has signed up.

– customize some form views and css without using admin

– In general, I need more php and js control to build what I need.

I need to build a reserved area page. When a user navigate to it, and it’s not logged in, he should see the forms. After registering or loggin in, he should see the contents.

I need to customise quite a lot of things, so, where can I find code docs?

It seems there are a lot of docs, but all for users, not coders.

Thank you, regards