Sum area values from shared parameters and put into a room tag parameter

Revit
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1

I have a project with appx 100 rooms, where I need to create floor plans with room tags, showing the floor, wall, and ceiling areas (m2).
The best way I found is to use the Revit roombook extension, where I can extract all the relevant surface areas and put them in schedules and into shared parameters of quantity id families.

Here comes the challenge:
How can I combine the separate wall surface areas, and put that value into a room tag parameter? The ceiling surface area should just be moved into a room tag parameter. Can you help me with the script?

So far I have used Dynamo once, but I believe in this case there is no other way to achieve this?
If you have a better suggestion of how to extract wall and ceiling surface areas of rooms (not just cube-shaped rooms) and put them into room tag parameters (so it can be seen on a plan) please let me know. :slight_smile:

(The ceilings for these rooms are not always horizontal. (curved, sloping, etc)