Resolved
The plugin wasn’t updating or reading the *.gmic files properly. After a few reboots and relaunches, the problem disappeared.
Changes
1 Since afre_darksky works with the rewritten afre_softlight now, I replaced the builtin with mine.
2 I moved the rewritten afre_softlight out of Testing and into the Colors category. It is an implementation of @DGM’s code, which in turn is based on a defunct company’s. I found myself using this soft light blend the most, so it would be appropriate for me to make a command for it. See I'm generating new blending modes for Krita - #51 by DGM. My old implementation, while trying to be helpful, was too complicated and would not be easy to use as a stepping stone for more complex commands.
As usual, update your G’MICs and their filters in a couple of hours after the diary entry.