I get this error on startup
Windows - downloaded the itch.io version
When you extracted it, was there a 'gradients' folder present in the same location as the exe file?
The error is caused if that folder does not exist
Oh I see what the problem is now, I accidentally included the files twice in the zip file.. :)
You've probably got a folder structure like this:
If you go into the Windows folder, you'll see blastfx.exe again, run that version and it should work okay. I'll get the zip files fixed later
It's worth grabbing the latest version I've just uploaded as got some updates the one you had was missing