This bug, or at least parts of it, still appear to be an issue in the current version of Vuo. Save Image to Movie is extremely inconsistent in how it records audio. Is there any update on this? Thanks!
You might find this documentation on exporting an app helpful. It explains that Vuo copies resources (such as your JSON file) into the app bundle's Contents/Resources folder, and how to make it not do that.
The original method of creating image feedback is both the clean and advanced one ;). Blend Image with Feedback is mostly a simplified version that does the basic trails and scaling. As color depth directly affects smoothness, the breaking point of feedback, and isn't easily set elsewhere without a blend node - it is absolutely important.
When that is said, the basic "hard" approach for creating more advanced feedback can look something like this:
This enables other displacements of the feedback image, here I'm using "Bulge Image", but any translation will do to offset the image to enable the feedback. This is also the approach you want to use for diffusion/reaction kinds of effects as you can blur/sharpen with each frame iteration.
As far as framerates goes, this should also be a viable approach. You might also have to hold the original image value to sync it up, but that depends on your composition.
The Blend Image with Feedback Node is missing a few parameters, I'm proposing a second node!!!
An absolutely essential parameter for feedback in my opinion is hue shift.
Also a "framerate" is very useful. So that not every frame is filled up with feedback, which allows you to create graphs etc.
There are also a bunch of parameters on "Blend Image with Feedback" that aren't very useful and can comfortably be scrapped to save space. Transforming the foreground image is redundant, and can easily be done with another node, similarly: width, height, colour depth etc.
An improved feedback would be soooo useful in my opinion.