Heroes 5 on a tablet.

The question arises: why doesn't the on-screen keyboard work, and is it possible to tweak something in the configuration files?

The on-screen keyboard isn't completely unusable; it just doesn't work in the scenario you described – it prevents starting a new map. It works within the game, but not fully. You can type names for saves and replays, although it's very inconvenient. As for using it as hotkeys in the game, I haven't tried that; I simply find it hard to imagine how that would work. As I already wrote, the mouse is quite sufficient. The interface is well designed for it. Regarding config files, I myself would like to know what can be changed