I went to drag a medium power line north ,so I pressed 'q' over the placed one and, not realising I had none left, I dragged a load of ghost poles. I removed the ghosts. After getting more poles, I went back and tried again to drag power north. As soon as it placed the first one, it made a line of p...

I'm having the same issue dragging large poles along a railtrack. When dragging from one side of the track to the other the game crashes.

I've attached the save. I've been connecting the large pole to power and dragging it along the rails eastward.

Same here.

Tried with and without mods.
Tried manually picking up coal and putting it in a box.

Error happens every time as soon as the coal gathering step completes.

I've just robbed most of the lines of bits for crafting stuff before i took the shot, theres no bottlenecks, but I see your point about direct transfer between assemblers.
I'll have to have a rethink

This is the most compact way I could find of making t1/t2 flasks. The lab/forge areas could be tightened up, but just the actaul assembly line I mean.
As it is it will keep 6 upgraded labs running constantly