Wile there are two people interested in use (test) this plug-in, I feel responsible to give few more explanations.
NOTE "room" = object created with room creation tool; in SH3D 3 or more connected walls don't represent a room.
When lance SH3D the plug-in verify if there are any rooms; if not is inactive.
After open an home plan it make the same verification; if find at least one room, the plug-in became active and could show the total surface even there are only one room.
If the home plane have multiple levels but not all own room(s) the plug-in will show and compute ONLY those WITH rooms.
At lance will make the total of rooms find on home plan. Then the user can check/uncheck the included surfaces in total.

@UbuntuBirdy maybe You're right but I don't find another criteria to make this.
Personally I've organized the home plan on multi-levels, some of them at same elevation or very close (<10 cm) for different purposes (electric, water and hot,furniture etc.).
Some of them have rooms some not.
The plug-in show me only those with rooms sorted by levels.
Unfortunately most rooms have "No name".
If You or someone else find a bather way I'll be happy.
Until there the rest of the necessary tasks could be made in LO Calc or MS Office.
I deactivate the option to open the csv file after creation because I don't know what could happen under different OS. Personally I don't like to open instantly.
Remember I'm not a programmer. I get start learning few month ago.
So, good luck [B-)]