Getting the following error while trying to upgrade belts by hand (not with bots)

lol wow had to zoom in a lot!Zeblote wrote:If you zoom in far enough, you'll see they already have couplingsUrbs wrote:I wonder how hard would it be to add couplings between cargo wagons. Its odd to see them like that as if connected by air.
orzelek wrote:Did you download latest version?
It seems that one you have is not compatible with Factorio 0.12.x.
Do these work well in 12.2?Tallinu wrote:I still like my version better - uses two fewer underground belts, looks a little less confusing, and can be built slightly narrower if desired.
billw wrote:Not really you just didn't build it correctly in the first place! Would need to see the track layout from before it broke to work out why it worked though.