Oli F

Yes, but the problem in your setup could be causing an error in the workflow, and by seeing the latter it may be possible to figure out the former.
 
Nothing immediately jumps as an obvious problem in there, so I do recommend you contact the authors.

This is iconic

Inspired by @Floating.Point's awesome SF Symbols Icon Generator Workflow, I wanted to explore how this workflow would be different if it used AlfredExtraPane's real-time preview feature. In addition, I wanted the workflow to not require usage of the SF Symbols app.
 
Presenting: https://github.com/mr-pennyworth/alfred-icon-maker/
 
Usage
Search for the SF Symbol you want to use. Icon maker will list all matching SF Symbols, and show a preview of icons using the selected symbol. For example, logo:
Press ↩ to generate icons in the previewed styles. For each style, it shows the icon in multiple sizes. This is the "style list view".
Press ↩ again to go to the generated 512x512 PNG file. Alternatively, you can drag and drop the icon.

Press ⌘↩ in the style list view tweak the appearance of the icon by entering the "style editing view" and typing the changes in Alfred in the format property=value. Icon PNG as well as the multi-size preview is updated in real time as you type.
The properties are:
color (or c) the color of the icon. background (or b) a comma-separated list of colors for the background. angle (or a) angle of the background gradient in degrees: 0 for top to bottom, 90 for left to right. radius (or r) relative radius of icon corners: 0 for sharp corners, 100 to make a circular icon. size (or s) percentage of icon size to the background size. The colors can be any valid CSS color keyword, or hex color code.
Here's an example of creating a circular icon with Italian flag colors: b=#009344,white,#cf2734 a=0 c=black r=100:
From the style editing view, you can directly access the icon by pressing ↩ or by dragging and dropping the icon. You can overwrite the style by pressing option-enter (⌥↩), or create a new style by pressing command-enter (⌘↩).
Notes on SVG to PNG conversion
We rely on Inkscape to convert SVGs to PNGs:
ImageMagick wasn't able to produce transparent backgrounds correctly. librsvg has a known bug where it can not handle the dominant-baseline of text SVG elements correctly. Without this, there is no way to vertically align text at the center of the icon. The suggested workaround of setting dy="0.25em" works only when the font size is exactly half of the icon size. ChatGPT and Claude weren't able to correctly write a swift program that would load the SVG inside a WKWebView and then take a screenshot. The PNGs didn't have the correct dimensions, didn't have transparent background, and in some cases, didn't use the "SF Pro" font (essential for rendering SF Symbols) either. Since AlfredExtraPane is able to correctly render the SVGs, it certainly seems possible to get the WKWebView approach to work. In the future, if we want to stop depending on Inkscape, we should revisit this.