RE: Form Customization in Event Management Portal
Hi Leo,
There are some OOB customizations for event portal:
Actually not all customizations require Angular update, let's review your requirements:
-> field creation: it could be done by adding custom registration field, then build a workflow to sync data from Registration Response entity record to contact field. (It'll generate more fields on event registration form)
-> dragging and placing fields: Angular code is required because we want to create a new contact record with more fields information from event portal, and it's complex to expand more fields for OOB registration form.
-> changing form: Angular is not required if you just want to change form layout or appearance.
-> adding images on Event Portal form: it's would be same as above, we can change appearance by css easily without js/angular code.
Example for change registration form:

Header background color(eventregistration.component.html):

change layout for firstname and lastname fields(attendee.component.html, by default there are col-md-6 and have same length proportion):

You could post any new thread in forum if you had encountered problem while customizing event portal, I'll try my best to give an anwser or thought.
Regards,
Clofly