After creating and exporting a custom shortcut keymap I should be able to import that keymap. This would be helpful when setting up Krita on another computer or when recovering shortcuts that Krita erased (has been happening often URGGGG!) Reproducible: Always Expected Results: In the Customize Shortcuts menu under Details>More Actions> menu there should be an Import Sceme option.
This is not a resolution to the problem, but the files containing these shortcuts are held in .kde/share/apps/krita/actions. Hopefully copying and pasting this directory provides a workaround but there's no guarantee it will work correctly. It may be best to wait until after the KDE5 Frameworks update before hard coding definitions for working with these system files.
The action files are actually krita-specific, they are a work-around for problems with KDE's shortcut editor and shortcut schemes. As you say, it needs to be fixed, but probably in the frameworks/Qt5 branch. I disabled KDE's shortcut scheme functionality in 2.9 because it was so broken!
Fixed in 3.0