I’ve done exactly that about six years ago in Ogre3D with C++. Now I’m about to port it into UE4. Will tell you when I’m finished. By now, you can look my source code [here][1] (look for the functions drawLevel4 and readLevel4Rec.
If you’re still looking, there are now some plugin tools to UE4 tools to help you use ESRI shapefiles and OpenStreetMap data to create things like landscape splines for roads and rail etc… www.terraformpro.com
Basically, it explains how to use the mentioned external plug-in from Isara, transfer the SHP information into Struct arrays and then how to draw lines and points in 3D in Unreal.