I have 8 boxes total and 5 were presented to Customs yesterday so this morning checked and tracking status updated to "Parcel at customs at country of destination" so immediately picked up the phone and call Pos Malaysia KLIA. Thankfully the call was picked up immediately but the person I dealt with yesterday in on leave today... No problem, the person I spoke to knows her stuff and she picked up immediately where I left off yesterday with her colleague. I gave her the tracking number of my remaining 3 parcels and she put me on hold for a few minutes while she search for my parcels... Few minutes later she came back to confirm the 3 boxes are at customs, now they have to wait for customs to inspect and after that only Pos Malaysia can give me the reference number for custom clearance. 

I took the opportunity to ask a little about the customs clearing process and my initial hunch was right!   Let's say you have 5 boxes and they are all detained at the same time at customs, how many times you get charged RM49.80 handling fee by Pos Malaysia is really up to the customs officer. If the officer is very busy and he manage to only inspect 1 of 5 boxes in the morning then he will issue one custom clearance form and pass it to Pos Malaysia. Then say after lunch he comes back and managed to inspect another 3 more boxes then he issues another form and next morning he inspects the last box and issues another form to Pos Malaysia. So in total there will be 3 customs clearance forms (for 1 box in the morning, 3 boxes after lunch and another box the following day) and Pos Malaysia will charge 3x RM49.80 because they were given three forms by customs.

So I was right about Pos Malaysia being a facilitator in this process, they have absolutely no control over customs. If you are really lucky and the officer inspects everything at one go then there will only be one form and you only need to pay RM49.80.

I forgot to ask another question and that is regarding "high value" imports, last shipment I had to pay additional charges because the value is above certain amount and there is an additional form to submit/declare... Additional cost there if kena this clause...

Well, I hope this is helpful to everyone importing their Legos and getting stuck at customs.