Thank you for responding, LonelyMax. I think your idea about a shared map of Ashan might be the only thing that can rekindle my interest in Heroes as a game (because I threw away my licensed copy of the sixth installment after just one day of playing). How many others are like me? I don't know...
Regarding the dungeon, I'm not sure – maybe that's how it was designed – but there are many transparent (or glitched?) textures in the dungeons and a few outside as well. This spoils the visuals. Or is it just my game that's not working properly?