I am running Kubuntu 15.10 and have had no success in finding an answer to the following question.

After enabling the desktop menu for application launch with right click mouse action (i.e. similar to Openbox) I can no longer access the previous menu for changing desktop wallpaper or changing mouse actions etc.

I have looked closely at the settings menu but have found no solution so far to access this functionality. Perhaps it is right under my nose but it appears to be hidden away.

left click to focus on an empty spot on the desktop then alt+d, Alt+s (holding alt when doing it) and the menu should pop up

also unless you disabled it there is an option button (called the desktop toolbox) on top left corner (3 horizontal bars)

Thank you for that. It worked for me. I had also disabled the toolbox which meant I couldn't access the desktop tools.