Looks like you're running into a problem with the Flash target.
While Flash is sometimes still valuable as a quick testing platform, it's also virtually unusable for publishing at the moment, since web browsers no longer support it, and third-party emulators like ruffle don't fully support the ActionScript 3 language and APIs yet.
Given this, not a lot of resources are devoted to Flash support right now, so if you end up hitting a bug, that's pretty much a show-stopper. I'd suggest just using a different platform for testing, such as HTML5.
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Having said that, here's the error:
Running command: BUILD
- Running command: haxe Export/flash/haxe/debug.hxml
Error: The input swf Export/flash/obj/assets.swf is corrupted
Perhaps you could try disabling the higher-scale assets in your project and see if that somehow fixes this (assuming you're not actually using higher-resolution scales)?
[Settings] > Web > Settings > Scales: make sure only 1x is checked
[Settings] > Settings > Advanced > Project Scales: make sure only 1x is checked
[Menu Bar] > Tools > Game > Clean Project
[Menu Bar] > Tools > Game > Cleanup Unused Files
Then try testing your game again.