this is a somewhat thorough list of rulings me and my group use in our sessions. one section per expansion. feel free to disagree 
since i didn't play any other expansions except for unhappy homes much (read: at all) i will update this list when i have adequate material.
Base deck rulings
Event card 'A stormy night' : the card that the event allows to be played may be an untimely death, since it never says we can't do that 
Event card 'Body thief' : may be canceled as it is played only, but not reversed when the players have resolved all effects. in other words, when announced, not when affected parties start removing cards from the table. 
When a card's effect is 'discard one card everytime you play a modifier, including this one' , even if the card is covered during the same player's turn, that player MUST discard one card regardless if he covers the offending card the very next second. 
When a card with the text 'discard your entire hand' is played, it's an automatic end of turn. 
Using multiple event cards that allow more plays is not allowed. that means playing 'misfortune favors the old' as the card 'a stormy night' allows us to play is forbidden. 
Unhappy homes expansion
Since the rules state discarding a mistery is a free play, we tend to discard all mysteries in our hand at once to make room for more useful cards (we barely ever get to use them anyway)
hope no one flames me for my long phrases