This game is supposed to have mouse support.
However, I can't get it to work. I can see no relevant game options.
In the DOS version, the mouse just works.
How do I enable it in ScummVM?

You sure it's not plain old disc rot?
https://tedium.co/2017/02/02/disc-rot-phenomenon/

This screen is shown when the "subtitles" option is turned on for the game. In this case it might just be turned on globally.
To avoid getting this screen go to the Audio tab for the game options, toggle on the box to override the global settings and select "Speech" for the Text and speech option ...

Every time you run GK2 or try to load a save, it keeps harassing you with this ungrammatical nag screen that asks you to download some unofficial subtitles.
I do NOT want them. However, I cannot find a way to disable this function.
If I submit and click "download", it just leads to a dead browser ...

So ScummVM does this not by changing the CPU cycles (like Dosbox), but by looking at each game's code?

How does ScummVM determine the correct speed for a game?
For example, how does it know how fast QFG4 is supposed to run? Is it just a guess?

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