Selecting custom fields on front end

Is there any way for a front end user that is creating an event to either create their own custom fields or have a choice of what custom fields to include on the registration form? For example, some of the racing events include t-shirts as a giveaway so we need to select shirt size on the registration form but this is only for some events and the front end users are the one creating the events so I am not involved in that process in the back end.

Thanks.

I would need this too.

Sorry Steve. At the moment, it is not possible. You can only manage custom fields for registration form from backend of the site, not from frontend.

Tuan