Hi F-D,
Please try packaging your project again for Windows 64 bit development and post the contents of your Output Log. To do this, navigate to Window>Developer Tools>Output Log.
Just before you start packaging, right-click and select “clear” in order to start with completely relevant data. After packaging is complete, Ctrl + A to select all, then cut and past the contents of the log into a text editor file and post here.
This should give us an idea of why your game is crashing. *One quick thought about this type of crash… Make sure you are using light importance volumes so each level is not trying to render off into infinity but rather, as the name implies, the pertinent areas of your level only.
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