Troubles on retrieving mass transit routes

Hi everybody,

Let's see if somebody else has found this kind of problem when using Elk.

I was trying to retrieve the paths of mass transit. Railway infrastructures are rendered really well as they are tagged specifically. However bus routes are not able to get rendered though Elk. Probably the problem is that they are used to be linked to existing roads and ways, so it should be some kind of conflict between tags.

I attach a fragment of Madrid and the data of a bus route in Madrid which is located in this OSM file.

Thanks!