FIS Wizard in fuzzy logic block not Loading Blocks after a Fresh Start up. Anyone Encounter this

I designed a Fuzzy inference systems in MATLAB R2015a, saved the file as an FIS file and loaded this file into the fuzzy logic controller block in simulink. For the first time, everything works perfectly. However, after quitting MATLAB and starting up at another time, the auto generated blocks between input to the fuzzy block controller and output were missing. All troubleshooting efforts were fruitless until i redesigned the same fuzzy inference systems afresh with different names, OR use a new fuzzy logic controller block every time i start up MATLAB. Having to this this every time does not seem right.

I used another computer with R2014a and simulink diagnostic gave a warning about the Mux block failing to update and asked to use the upgrade advisor, after which everything runs again, but nothing like that in R2015a.

Does this have to do with the versions? can anyone provide a solution.