Actually I found a case where it does matter. If you have multiple Rename Glyphs parameters! So I tried to make something work with only one of the Rename Glyphs. That did not work. Only after implementing 2 of them and switching their order back and for, I figured that this totally has an effect.
Unfortunately there is still something weird happening with the instance preview. It doesn’t show what happens in the final export. So I always need to export and open the .otf to check the result.
@GeorgSeifert I sent you a file last Friday which shows that problem. Only the approach with two Rename Glyphs parameters is a new discovery from today, so if you need a sample setup, please let me know.