The interactive schedule has to use the calculation units so you have no choice there.
Calculation units also seem to be the only place where you can set a volume unit.
The zone stamp 02 21 I notice has an option where you can choose the units you want to use for the area - so obviously the stamp can override the calculation or working units as set in Archicad - for areas at least.
You would need a zone stamp that could allow you to choose the volume units as well.
I don't know of one but a lot of people talk about the 'Master Script' zone stamp - from memory that seems to have a lot of options, not sure if it has volume units - (if it is still available?)
I assume it is possible if the areas can have a choice of units it should be possible to do the same for the volume units.
The problem will be either finding an object that already does this or scripting it yourself.
One of the forum moderators.
Versions 6.5 to 25
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