An example below, if I copy smelter 1, and paste it at 2, there's no inserter between the buildings, and the inserter which should be at the side of the building is now in the middle.
This does not produce an error, and seems to be easily fixed by taking a copy which is closer to where you want to build. If I copy the last smelter which work as expected I can paste in the 2 location and it builds everything just fine.
An example below, if I copy smelter 1, and paste it at 2, there's no inserter between the buildings, and the inserter which should be at the side of the building is now in the middle.
This does not produce an error, and seems to be easily fixed by taking a copy which is closer to where you want to build. If I copy the last smelter which work as expected I can paste in the 2 location and it builds everything just fine.
Coordinates of the build, in case relevant:
50° 23' S 162° 07' W
50° 22' S 170° 57' E