The Registry entries CoX expects are all manufactured when missing as it starts up.
If you don't start it with -project <something>, look under HKLM\Software\Cryptic\CoH.
If you use -project xyz, look under HKLM\Software\Cryptic\xyz.
If you run the test client, it is wired as if it uses -project CoHTest, hence its key values are under HKLM\Software\Cryptic\CoHTest
The only thing missing you would need to manually fill in, if you really had a server to talk to, is the Auth key value's IP address. This is how SEGS works too, although they are using an I4 client atm.
Btw, is there a little friendly competition going on, I4 vs. I23?

))