During gameplay, the game randomly opens up the inventory screen of one of my characters (Use which Item ?) and simply refuses to take any inputs. Mouse stops working, keyboard shortcuts wont work either.

Game is running on the default GOG settings.

Also, mouse inputs (Movement for instance) often procs twice. Its probably a timing issue. Bonus cookies for everyone giving a hint on fixing that too ^^

It seems like some of software interferes with DOSBox or some of your keys is stuck. It is a "feature". E.g., if you press "shoot" twice in rapid succession, it will count only as one turn (and enemies will move only 1 cell toward you, not two).

As for keys, my keyboard driver tells me that everything is perfectly fine and no key seems to be stuck or "on the lose". I even let a logger run while idling to see, if i had random presses: Nothing.
And its the only DOSBox game that does it. World of Xeen for instance doesn't have the same issues.

As for the other issue, its the opposite. one click is registered twice. Say, i click on the upper left corner of the dungeon view window (turn left) and instead of turning 90°, it does a 180° turn or moves two tiles etc.

So, from what i could gather, it randomly happens with characters who died in combat. As soon as they are dead, their inventory pops up and the "Use" command is prompted and softlocks the game (Music / SFX plays, mouse freezes, keyboard doesnt register)