Changing kerns to a kern group is problematic

Renaming kerns to kern groups doesn’t work well. For example, I have kerns with c-deva on the left and other glyphs on the right. I need to turn c-deva into a the group @c-deva. If I try to do this the group becomes “@ @c-deva” and the kerning doesn’t work. But sometimes it works if I close and reopen the file after changing the group name—the group becomes @c-deva. I discovered this accidentally because renaming groups tends to crash Glyphs. I can use Tosche’s copy/paste script to copy the kerns to a new group without renaming, but I get the impression that just renaming would work if the process wasn’t hampered by multiple bugs.

Edit: closing the file after naming does not always work. One of three things happens, and which one happens seems to be random:
1 - The new group name takes effect
2 - The group name is now @@group instead of @group
3 - The group name remains unchanged.

Edit: when it seems like an @@ group is now just an @group the name can change back to @@ when opening the file again.

Where do you edit the kerning group? in the info box or the kerning panel. The kerning panel does not support changing glyph to class kerning (yet). fill the group name in the c-deva, kick the entry in the kernig panel to get to the pair in the edit view and close the locks in the info box.