Hi, I was just sending myself a live preview to check out this awesome feature and I noticed that the %chance did not change after I selected the Finishing#2 reagent.
Yes, it did request an update (this message in the top right) and I waited until it finished, nothing changed.

In the screenshots I have the normal crafting and live preview with and without finishing reagent.

the crafting costs are adapted though hmm
can you check if the brood salt changes your inspiration in simulation mode?

Yes, simulation is adding it.

Live Preview backend reworked in 7.0 (upcoming)