When you held shift, and tried launching the exe, nothing happened? Make sure to hold shift down the entire time, even after double clicking.
You’ve said other Ren’py games work, but could you verify if you’ve got any other Ren’py 8 games around and see if those are working? Most Ren’py VNs run on Ren’py 7, but Ren’py 8 officially released June 26th 2022 and this is one of the first VNs on F95 that I’ve seen using it, so there could be something on your system messing with the new version’s ability to run.
Like Aereon said below, you can try running the Ren’py 8 SDK test game to see if it’s an issue specific to IWH, or if it applies to all of Ren’py 8.
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