in sabah and sarawak, yes. usually used by the natives.

so u shud know how disappointed sabahan n sarawakian in selangor are.

go into churches that have indonesian sermons.

or orang asli churches in pahang/terengganu. Some even small huts in the forests.

you never see or heard them because the most common in peninsular are english, mandrin and tamil.

indonesian service usually starts in the afternoon and only some churches have it (where indonesian workers are living nearby)

and yes, its a proper term.

when translations are done by the missionaries, they use the words most familiar to the locals.
Allah being a known term for the Supreme Being, and it so happens has the semitic root words in hebrew and aramaic. so it became the proper translation in the malay language.

Ah don't get fooled by the local propaganda.

The word "Allah" predates Islam.

Which means before Islam existed, Arabic already use the word allah to refer to God.