@pichlo - thanks! The reasons are very understandable. Maybe you could try tomorrow again, on the way back from work. Assuming that it will hang too. If it will, please attach gdb to it and obtain backtrace:

1. find out which process is running pure maps
2. gdb sailfish-qml pid
3. in gdb: thread apply all bt

Ideally, you should do it via terminal login (ssh). Or maybe there is a way to get backtrace dumped into file.

Check in time whether you have gdb installed.

Other replies below:

Re rendering: That's my take on it as well. Mapbox GL maps are surely better styled than the one I made with the server. Here, help would be needed by someone wishing to learn how these styles are made and how map tile data is structured. I don't foresee when I can deal with it myself.

Re instructions: assuming that you used Stadia, its surprising, but possible. I expect that we use somewhat different Valhalla's settings and imports could be done at different time (maybe some road is closed at OSM).

Hot device: I wonder whether its related to smooth position marker. But device even before it was occasionally warm for me as well.