Not an answer to your question - Instead, a follow-up rhetorical question that may make your question redundant.
Does the order of the stack make any difference to the result ? … Perhaps, as is true for PhotoLab, the order in which filters are applied (or corrections, in the case of PL) is fixed & determined by the software itself … regardless of the sequence in which we action them (?)
Having just reinstalled Color Efex 5 I have now found out that if you get just the right bit between filters you can click on it and drag, changing the order of the filters. I don’t know if it’s just me but, on my 32" 4k monitor, it takes a fair few clicks to find just the right spot to enable dragging. I reckon simply clicking and holding on anywhere at the top of the filter would be a far better implementation.
Yes. An more obvious example would be colour gradient followed by B/W conversion (resulting in a b&w pic) or the other way round (resulting in a coloured pc). Or maybe adding grain first then detail extractor the other way round… very different results.
@John-M Well, all of them really as when I do certain things to achieve a certain outcome, as shown in my examples above, stacking order affects that outcome. If I am working on am image and decide it needs a touch of “Glamour Glow” then I will add it but will need to place it where I want in the filter stack to get the effect I desire, not just at the bottom. I will also experiment with different combinations and orders of filters if I have no fixed idea of the final image I want and seeing what changes filter order has on the image is part of that process. Give it a go and see