I'm going to have to go through a similar process very soon. My plan as of now: If it is a rectangular room - you can save as "rectangular jpeg" in CC3. If its an odd shaped room - then my thought is to export the whole image to photoshop and crop out the rooms I don't want. You may want to also check the CC3 forums to see if anyone else has looked into this. I know there is also a new entry in the annual that has a "cut" function which may be applicable.