Welcome on board the SpatialOS pirate ship! Let’s get your issue sorted.
Even if I understand that you have followed the directions to the ‘T’ I will still need to ask you some questions to get an idea of what is going on.
From what I gather you are at step 6 of the Pirates tutorial. Could you also please confirm that you are indeed using version 12.0.4 of the SDK? It might be that you are using 12.0.0 which should be fine but it is better to switch to 12.0.4 to take in some extra bug fixes.
After adding the component definition to your schema file (and saving the file). Did you indeed use the menu in the Unity editor to run
Generate from Schema > Build
and generate the corresponding source code?
If so, and after making the other changes, did you follow the steps to rebuild all necessary elements, i.e the snapshot regeneration and building the workers?