Hello,

We are customizing the Events module, and as we need to add some fields and as this will not be a long term project, we are just adding custom fields by editing the "event.registration.form" view directly with the Manage Views option in developer mode.

Everything works fine, we already added most of our custom fields, but, we need:

To add an auto sequence number field that increases automatically with each new record.
This sequence must have a format as US-2013-001, where "001" will be increased each time.
In the Manage Views fields options we can't find how to create this.
We also found that in Settings - Technical - Sequences & Identifiers, you can create a new custom sequence, but we don't know how to relate it to a field to be added in the form.

So, in resume. How we can add a sequence field number with the manage views option to our Event registration form?

Thanks!