route calculation error

I have a GPSMAP 62s (firmware 2.90) and use, obviously, the OSM Maps from
I upload the gmapsupp.img
I have problems routing to waypoints from the device: When routing to a more distant location, say, as little as 150km away, I often get the error “route calculation error” after the route was calculated to ~50 or 80% on my device.

Is this a known bug, is it related to the GPSMAP 62, to its firmware or is this an issue of mkgmap?