Selecting a Record Type when Creating a Record from an Online Event
When creating a record via related lists on the Event detail page online, it is possible to specify a record type. To enable this feature, grant access to the SObjectRecordTypeRedirect Visualforce page. If the user has permissions to multiple record types, the record type selector displays after selecting the New button from a related list.
This feature is not supported for objects with specialized creation UIs, such as Event Speakers and Attendees.