Yeah, I must be stupid or something ... I created this test to convince myself, but all the while I just had a wiring problem in the problem situation.
Came back to retract my post, but alas, someone already seen it ;)

Let's see if I can find a way to close or remove the post.

Sorry to have ...

IGNORE THIS, I WAS JUST BEING STUPID.



I confirmed with just base Space Age content; selecting All Belts makes the graphics do the correct thing, but the item count is still only for the single tile.

Version 2.0.77, build 84539 mac-arm64

See screenshot; the count is 3 but there are clearly 14 ...