Page Down button not working, Can't create tunnels

[Smelly wet fart]

Hey, I'm in the middle of creating a custom map on the editor for me to play later, and I'm in the middle of putting highway connections in, however I can't create tunnels, the page down button doesn't work. It's not the keyboard because I can elevate the road and then lower it (meaning the button works fine) but I can't lower the road below ground.

I tried activating some of my mods like road anarchy but then when I tried to force the road to go underground either it would have the tunnel there but it would just be filled in with grass and not look that nice, or it would lower the road but not make a tunnel or lower the ground with the road as well? Anyone know a fix to fix this?

[Avanya]

Tunnels are not supported in the map editor. To make tunnels in the editor, you will need this mod. And they'll look a little weird, but just ignore that. They will look right in the game. :)

https://steamcommunity.com/sharedfiles/filedetails/?id=645390478