I'm sorry, it appears I misunderstood what you were asking for. I thought you were having trouble finding the code in the dynamically created .DLL that is checking your registration status.
So what you are actually asking is how the .DLL is stored in the original .EXE, so that you can modify the .DLL before it is extracted (and crack the code in the .DLL that checks your registration status, etc)? If that is the case, I'm not sure I can help you... Without knowing what packer/protector is being used to encapsulate those .DLLs, or which specific application you are working on, I have too little information to go on to even hazard a guess.
Sorry I couldn't be of any real help.
Regards,
Satyric0n