You can write to CEE SG to express your interest to be on the waitlist. The email address is: ceespore-pr@catholic.org.sg. 

There will be some slots on waitlist , once someone withdraws the slot will be released and you can register yourself. It is on a first come first serve basis. However if you have written to the ceespore pr email address earlier to express interest to be added on the waitlist we can also assist you to be registered manually. 

There will be no refund of payment because CEE needs to secure logistics and handle financial matters in advance prior to facilitating the weekend.  Do note that instead of a refund, you can try and modify your registration to select any of the other weekend dates.