First of all, I would like to comment on the job well done coming back to Phonm Penh safely. I think there has to be some exciting moment like a sand truck passing by at 80kph besides your Piaggio. That's gonna be super sketchy.
As for @ahleap kitchen window, that looks just like photoshopped view. Absolutely stunning!
About the Ape service and maintenance, the model has been existing for 80 years in the planet earth I guess(probably longer at the planet of the apes), there's for sure free resources around. Here I found you something, and hopefully it works for you.
Service manual download
http://das-apenteuer.de/media/Downloads/piaggio_ape_servicemanual.pdf
Watch Rise of the planet of the apes for free at fpxtv
https://fpxtv.com/free-rise-of-the-planet-of-the-apes-watch-online/
I think 20w50 is common and safe to use engine oil for all around warmer climate region. Since the engine is still new, I think it's worthy to invest a little bit more extra on a lighter weight oil as 15w40 suggested in the service manual. I'm not exactly sure if this engine require a 2T, but that's what was suggested in the service manual.
Shell Rimula R4 X was once my favorite engine oil some years ago where the guys at the car club challenging to drive a super low speed with our fuel guzzler to make them fuel save, and stretch engine oil change up to 10,000km per cycle. Problem is, it's diesel spec, and not anyone of us dare to stress the engine rewing speed.
added later: scratch the 2T, just reread it again, 2T is for 2stroke petrol engine. Yours is a diesel 422CC engine, so do not require 2T.
Malaysia got orangutans, doesn't have any ape 😂
On a serious note, we don't have tuktuk here. So I don't really know if it's possible for me to import one and make it my ride. After reading your reply, i went search for Ape cross and found this YouTube video, feeling impressed