I think I have found an issue with the route calculated by Kurviger
Here is a url to a short example that shows the issue:
I really can’t figure out why Kurviger isn’t taking that mountain pass. I have no restrictions active, and as far as I can see (I really looked ) there is no gate or access restriction in OSM
There’s only a maxspeed, the type of road (tertiary) and the name of the roads set.
Is it because of that small river there? I’ve never seen Kurviger have problems with that, I would be very surprised if that 's the case