I am implementing a \"locking\" system in my app which protects my app against being copied and used illegally. The system checks the signature of a hardware-based code and
There's a certaining amount of misconception about signed assemblies. Assembly signing is not, as mackenir pointed out, a secure mechanism to be used to prevent your assemblies from being tampered with. The following article on codeproject gives a pretty good treatment of the subject:
http://www.codeproject.com/KB/security/StrongNameExplained.aspx