yeah, that is being added right now. There will be args like '-nostatic -noitem -nomulti' to exclude static tiles, non-static items, or multis.
I've tried it out on existing static buildings and it seems to work just fine with UOAR, even doing partial extractions.
Note, it will also write hue information on items to the multi file but of course, UOAR will ignore that and if you import it into UOAR, fiddle with it, and export it again, that hue info will be lost.
here is a partial room extraction with z limited to 0 to 30 from the Sweet Dreams inn

or the healer with the roof cut off