This is caused by integer overflow - if the result of an operation exceeds the range of a 32-bit integer (about 2.15 billion) it will wrap around and become negative.

It's just a graphical glitch - as you can see in the picture the inserters' arms are 90 degrees offset from the direction they are supposed to be pointing, which shouldn't ever be possible.

The inserter arm orientation doesn't seem to get rotated in the blueprint preview.

I'd like to make a comparator setup that filters signals based on a constant combinator. This is currently possible, but kind of unintuitive. It would be nice to be able to connect a combinator to two separate input networks and have it perform component-wise operations on the signals.

I propose adding a new mode of operation to roboports that would send all materials required for construction (and that a bot is not yet assigned to) to the circuit network. This would allow you to, for example, build a train system that automatically delivers the construction materials on demand af...