And you have it correct. The only thing going into the black tank is the toilet. Every other drain/shower/sink in the system goes into the grey water.
Although I believe that some older years had the shower also going to the black tank.
Call up Cruiser RV and they are more than willing to sent you a manual. I think if you search this site you can find the phone number.
20XX 3/4 something TBD
2010 K-Z Spree 318BHS LX