I only got to run 1.1... not 1.0. I did NOT generate the backgrounds... I "assumed" it would simply run with a blank background (to test the theme of course).
That's what should happen, if the "blur" category is not defined it should work with a plain gray background. One thing to note is that inside the zip file there's a Arcadeflow_11 folder, that's the one you have to put in the layouts folder. If you unzip the archive you'll probably end up with a Arcadeflow_11 folder INSIDE another Arcadeflow_11 folder, which would not work. Sorry that was my mistake in building the zip archive.
I also tested it with a 320x200 window resolution and it works, so maybe the issue is with the Pi itself.
P.S. thanks to this low resolution test I found a small issue with thumbs zooming: since the zooming item is a surface, the image content is at the resolution of the small tiles, so it gets pixellated when zooming to larger. I'll tweak the theme with a prescaler so that the image looks crisp when zoomed, and scaled back to the smaller size. That will look much better for low res screens.