the current module is very restrictive and doesn't allow for flexibility. for events that require a qualifying donation made during the year, there really is no way to set this up as a one step process. you need to set up an RSVP event and then link to a donation page in the confirmation. Alternately if you set up as a ticketed event with a $0 ticket and then use additional donation, this is misleading in that no one is actually purchasing a ticket.