No. It's a Python generator that writes a normal mesh. There's nothing to apply or bake; the result is an ordinary mesh object with material slots and UVs, and it exports to any engine like any other mesh.

Yes. Press Convert to Plain Mesh first, otherwise your edits are replaced the next time a setting changes. Separate by Material does the same and also splits the parts.

A hall at Medium tile detail is about 50,000 faces; at Off it's about 10,000. The roof alone at Off is about 5,000. A five-storey pagoda at Medium is about 85,000. Generation takes 0.1 to 1.2 s depending on the preset and detail level.

Yes. All lengths follow your scene unit scale, and presets are converted from metres when you load them.

A shrine hall is an irimoya or kirizuma hall with natural wood and a cypress-bark roof, which the presets cover. A bell tower is an open hall with no walls. Castle keeps (tenshu) with stacked chidori gables aren't a preset yet, though a karahafu or chidori gable can be added to any hall.

They follow the usual proportions of Nara- and Heian-period temple architecture, but every setting is adjustable. The presets are starting points, not reconstructions of specific buildings.

Yes. Buyers get all future versions.