I had an odd behavior today I've not seen before. I had a paint layer would not let me edit and, in fact, displayed the message "Group not editable" whenever I tried to make a mark on that layer. All the other layers in the group can be edited. The problem layer in the example below is "trees" and you can see that it does not appear to be a group but all the layer movement controls are grayed out. I tried dragging it around in the layer stack as well as reordering other layers, all to no effect. Finally, I duplicated the layer (the "trees" layers above it) and was given a normal, editable paint layer. I'm sure at some point in the workflow I had merged "trees" down one or more times but I don't recall making it its own group. Not sure now what to do with this rogue layer other than change its visibility and leave it alone.

Anyone seen anything similar?

Huh, that's an interesting one. Could you make a bug report and share the .kra file with us?