GF for Event organizing?

- We need to put the form on a post (type) along with a description text and other fields.

Gravity Forms can be embedded in a page, a post, a widget or a template.

- Only logged in users can submit an entry and only once in the form's lifetime.

You can satisfy this requirement with the "no duplicates" rule on the username or email address.

- For events with limited seats we need to limit the total number of entries.

You can limit the number of entries per form.

- Easy duplication of previous forms for similar events, templates maybe?

Duplicating a form is a one-click operation in the form builder.

- The form must have a opening and closing date.

This feature is included as well, and you can show alternate content when the form is not visible because of these rules.

- The user should be able to edit it's entry while the form is still open.

If you mean the user should be able to go back and edit their entry before the form expires or event passes, this is not a built in feature of Gravity Forms. There is no provision to let a user go back and edit their entry. You could probably do it as a customization, pulling up entries a logged in user has made, let them select the one they want to edit, then retrieve the values they submitted and pre-fill the form with them. They can change whatever needs to be changed, then you could update the existing entry and delete the new entry which would be recorded for the edit. It's not built in, but it could be accomplished with some programming.

- Some users might be banned from events altogether, this is noted in the user meta data. Can we hook into pre rendering of the form and display a error for those users? We have experience in WP development.

This is an interesting on. You can use the gform_pre_render filter to prevent a user from seeing a form. You could apply a gform_pre_render filter to all forms (or just select forms) to always check the logged in user's meta to see if they are blocked from events, and if so, not show the form and show alternate content. Or, you could do this before Gravity Forms is involved by protecting the page where the form exists, or wrapping the Gravity Forms shortcode in some sort of shortcode or function to check the user meta and see if they are banned from events and thus should not see the form.

Let us know if you have any more questions.

You can make the form available only to logged in users. That way only logged in users will be able to see the form, and you can capture all their user information. It might not be available in the demo.

You can pull usermeta into an entry using the default values, and merge tags, for logged in users. Merge tags are documented here: http://www.gravityhelp.com/documentation/page/Merge_Tags

You can perform calculations on the entries and tabulate the information however you like, and use it nearly wherever you want.

We can give you more specific advice on how to accomplish your goals in the regular support forums, rather than pre-purchase forums, after you have your Gravity Forms license.

How far have you gotten with this already? Please share the code you are using to display the list of users and we can help you display them in alphabetical order. If you have not already purchased Gravity Forms, we'll provide support for that issue once you have a license, in the regular support forums. http://www.gravityhelp.com/forums/forum/gravity-forms#postform