There are probably illusory walls somewhere in the room. Try equipping a torch and walking near them.
You can destroy walls with fireball/shockwave potions and it can make your way easier but this shouldn't ever be necessary to reach the end of the dungeon.
We are planning to add keys remapping later on in development, thanks for confirming that it's needed. Also it might be more convenient for you to scroll through actions with mouse wheel, if you're using a mouse, or through 'A' menu.