Copy protection software can work with different methods, but "inject codes to the end of models" does not make much sense to me. I doubt that this works and don't see how this could help with copy protection.

There are many copy protection solutions on the market. I am not this familiar with them that I could recommend a particular one. But I suggest that you do a Google search and check which software meets your requirements. Gamestudio should work with all normal copy protection methods, but not all versions support everything. For instance, you'd need the Pro Edition for using a software that modifies the EXE or the engine DLL.