When you need to know what happens to your registry when you reg a Dll just execute the following regasm command and have a look in the created regfile.
This Command only creates the regfile. It will not register the dll.
RegAsm.exe mySuper.dll /regfile:mySuper.reg "C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\RegAsm.exe" mySuper.dll /regfile:mySuper.reg
