The thing about Taoism/Chinese folk religions is that they believe the universal law applies to every being on earth regardless whether they believe in it or not. In other words, if a group of English-speaking Christians decide to band together to do good for the community, they will be judged accordingly to their actions and not who they pray to.

On Kusu Island, they even have a deity they pray to who is MUSLIM. Lord Datuk. Before going to the island to pray, the people who want to do so cannot eat any non-halal food beforehand. Lord Datuk's shrine even have Islamic prayers poster(?) stuck on the inner-walls of the shrine.

Buddhism is about receiving enlightenment and escaping the cycle of rebirth. The theory is that all Gods, Demons, and whatever creatures exist at one point but they reach the level they were at based on their Karmic seeds sown over many lifetimes. The Christian God is basically someone who has accumulated too much good Karmic seeds to the point that he gets to rule the world for many centuries but eventually when the Karmic seeds are exhausted, he will be "demoted" back to being of a lower plane. Same goes for the ancient gods of Egyptians, Romans, Greeks, they all existed at one point and slowly died off.

Hindus are much simpler, they believe that all religions are created by One Ultimate God to cater to different audiences, cultures and languages so it really doesn't matter who you pray to.

These are just what I learned from various people over the years but my knowledge are a little rusty so if there's any inaccuracies please feel free to correct.