Hello
my first idea if i was in your situation would be to try to make the brush under the road invisible (and set some visible things upon it on road sides). In Hope it helps.
You can add more control segments in your spline to adjust for the spline showing under the landscape like that. All you need to do is Highlight the selected segment square > Hold Cntrl > LMB-click to add control point between the other two in that segment.
You can tweak Pitch and Z values of the closest control point to raise the road, or you can just lower the terrain to the road’s height. And you need to enable collision for every segment if you dont want to fall through it.
In our Twitch stream from last week we demoed the Vehicle example that’s available in the Marketplace now. In this demo we show how to use splines for the most benefit. You can take a look at the video here. This video starts at the 22:09 mark for the example with splines.
In regards to the pointy areas you can add multiple points in these segments to get the look and feel you want. Then start removing some of the points between and the spline will rebuild mostly holding that same shape. I use the additional points, much like in the video, to achieve the look and feel I want then edit it down to what is actually needed. Give it a try and see how it all works out. Make sure you are clicking the ‘All Splines’ or ‘Selected Splines’ to rebuild to make sure it gets the look you want. Also play around with the settings in the detail panel.
As Jacky mentioned using the pitch and z values will bring the landscape up to match your spline. Clicking more on the all splines or selected repeatedly will even it more out in chunks.
If you need further help just ask and I’ll do what I can to help out!