Thanks for your replies.
Below are more "standard" rules of this friend that i would like to clarify also:
1) Why is it that if a person calls pong, shows his pong tiles, he cannot cancel and take back. But in the case of chi, can take back after showing?
2) Normally, if someone throws the winning tiles, he pays double. But for special sets like shi san yao, da si xi etc, her rule is that everyone will pay double. Technically, no difference from zhi mo. Her rational is because these are special sets. Only got to know about this rule when she threw a hong zhong for me to win shi san yao. Other players were saying they should not need to pay double, but she insist that this is the standard rule.
3) normally, if we throw a big tile which results in a player getting 5 tai or more, the person who throws need to bao. By her rule, in the case where a person already has 5 tai (eg. 5 tai for flowers and animals), if another player throws a big tile and this person HU as eyes, the thrower also has to bao. My understanding is that only if the big tile results in another tai, then need to bao, which is not the case for eyes.
Are any of the above standard rules for you?