When can a person cancel his loan facility without subject to any cancellation fees/penalty? 

No early settlement penalty when the loan has past its lock-in period... really depends on the loan agreement when you sign with the bank... 3years, 5years, or some even no lock in period.

What about in the event when the Purchaser decided to cancel the loan, after the loan documents were stamped but before the loan were release? 

then the purchaser must have a very good reason to do so... meaning he will finance for the purchase from his own bank account or in cash. If signed and stamped... maybe still have grace period, but i am not too sure if can cancel and pull out at the 11th hour...

your cancellation mean after loan disbursement or after sign offer letter but before loan disbursement?

You have to read the terms & conditions properly.

After offer letter was signed but before loan disbursement. 

should be no penalty before disbursement. but the respective bank may not want to approve yr loan again in short terms... you may refer to the T&C in contract

Maybe will be reflected in 

Central Credit Reference Information System (CCRIS)

Kamsiah! 

Apparently the content is too short...zzz

CCRIS wont show if there is any penalty. only application record on type of loan. successful, pending, reject...

Yes agree with @Ngoi, it will probably show up in the respective bank records only... 

@Ace thanks for sharing