Really loving the new gui elements with the white line and red cross-thing. The crash only seems to happen when I place one belt too quickly after the first one in its pair, otherwise, it's working great! It even fixed the issue in the save I kept in case you wanted to be able to reproduce the bug.

https://i.imgur.com/OSWS8r4.png

Thanks for report! How fast was this too quickly belt placing?

Please try the new version.

And again, the fast replacement was disabled.

It was happening within a couple seconds of placing the first belt, if it helps.

It also happened while I was dragging them, as if trying to place them like normal underground belts.

Is it 0.0.6 or 0.0.7?

I don't remember, but it doesn't happen anymore, and afaik my version of the mod is up to date!

Nice, thanks for response!