Why does my Simulink model work when I export it to the previous version (V8.2 to V8.1)

I'm following a tutorial on how to model a power electronic circuit in Simulink Version 8.2 (R2013b). The tutorial uses Version 7 of Simulink I believe. I was able to follow the tutorial closely until the tutorial created a mask for a subsystem as the GUI layout was different in the tutorial from what Version 8 has. I managed to create the mask and that part seemed to work fine. When it came to the simulation though, there was no output from the scope. I exported the file to the previous version (8.1 R2013a I believe) and lo and behold the scope gave the same output as was in the tutorial. I'm not sure why this worked and it would be good if I didn't have to do this for subsequent tutorials which I will be following.