The crashes are being caused by out-of-bounds route nodes in these positions:
{x=8, y=8, z=-2}
{x=8, y=3, z=-2}
{x=48, y=8, z=-2}
{x=48, y=3, z=-2}
You need to correct the respective map block file.
It's too late for the save, as the map has already been generated, although you can edit it with a text editor and change every node with position "-2" to "0".