terrain blocking underground tunnels

I attempted to make an underground tunnel by placing a standard tunnel on a section of track and then using the terraformer to raise the terrain over it, leaving the entrance and exit above ground. The problem is, than when the train enters the tunnel, you can see the terrain blocking the track. Of course the train continues through it without a crash, but is it rather disconcerting. Is there a way to clear the tunnel, or is this a known issue with NL? Using NL for Mac, if that helps.
Mike

Tis' a known issue with NL im afraid, so you'll have to put up with it, and also i dont think anyone would be mean enough to rate your coasters down because of it. You can also disguise to terrian by using 3ds objects

This is my first post here so I want to personally thank WWS for everything he's provided for all of us. Thanks Weeweeslap! Anyways, it's cool someone asked about this. I was wondering how the tunnels were done on one of my fav tracks La Cordillera. I can see now they did it with 3ds objects. I've also see some just use tunnels and not worry about obvious terrain texture. I was thinking, would it be possible to fashon supports to disguise it? - Nyssa