I think there is a bug with the road tool. Sometimes a road will generate a high spike.
Before, it usually happened when a node was placed at a wrong elevation in map overlay mode, but this time it happens between two road nodes.
The problem seems to be tile related, moving the local road nodes change the bug, sometimes to a different spike, sometimes to an elevation cut, always right where the tile limit is:
It happened to me a few time after the last update, but I can't find a real pattern, except the tile limit thing.
Other bug, sometime updating a road will delete the first road node.
As you can see in this screenshot, the first section of the runway is visible, but not a part of it if I select the road. If I update it, this first section will disappear.
You can also see a bug in the transitionnal area around the road close to the runway. Again, it's exactly located at a tile limit: