In K3b, select Settings->Configure K3b and click on Devices. Under Reader, next to Cdrdao driver, click on the setting in the right hand pane. It will turn into a drop-down box. Then click on the drop-down box, select generic-mmc from the list, and click OK.
The easiest way to change the mount points back to their original settings is to edit /etc/fstab with a text editor (you'll need to open it as root).