1a. When you remove the occupied rooms, do you lose the possible 1/2 points you receieved when placing the rooms (in the upper right of your hotel)? My guess was no, but I am not certain.
1b. When you remove the occupied rooms, if you no longer meet the conditions of a previously claimed Politics Card do you lose the points? Again I believe this is a no.
In summation if you lose occupied rooms is the only penalty the 1-4 points for the room and possibly some points from an end of game scoring guest?
2a. If you get the bonus on the C2 emperor tile and place a room in the upper right hand corner of your hotel board do you score the bonus 2 points?
A) no. you don't lose those points. In fact, you can get those points a second time if you are able to fill those rooms again later in the game.
B) No. Once you place your marker on a politics card, you get that benefit forever. For instance, if you are playing the politics card that says you get 15 points for being the first to 20 Krones, you don't lose the 15 point marker spot if you subsequently spend money to drop below 20 Krones.
2a) The only penalty for losing occupied rooms are the end game scoring bonuses for the row those rooms were on, plus any staff bonuses associated with those rooms being filled (which no longer are).
I believe that you score the 2 point bonus for doing as you say, although I'm admittedly not 100% sure on that.