I've encountered an issue several times where industries won't supply lines that very far away. I don't seem to recall reading anywhere that there is a maximum distance that cargo can be shipped, but perhaps there is? Has anybody else encountered the problem?
I've encountered it on two large custom maps, where there are only a few industries spaced quite far apart:
http://steamcommunity.com/shar…filedetails/?id=805773929
http://steamcommunity.com/shar…filedetails/?id=796639420