Under macOS Sierra if you trigger an "Open Items" shortcut and get an error message similar to the one below then do the following:
Open the "Open Items" shortcut.
Where the "Open With Default Application" pop-up menu is select "Finder" from it.
The shortcut should now look like this. Save and close the shortcut window and this "Open Items" shortcut should now work.
You will need to do these same steps for all of your "Open Items" shortcuts.
QuicKeys 4.0.7 and Lion
QuicKeys 4 - Mavericks/Yosemite/El Capitan/Sierra