The compiled help file (.chm) should always be delivered to the same directory as the XLL file.

It is often convenient to deploy the XLL to the same directory as the wrapper assembly. Then you can use simple code to find it when it needs to be loaded, e.g.:

CopyC#

string theXllFileName = Path.Combine(
    Path.GetDirectoryName(typeof(ApiTest).Assembly.Location),
    "ApiTest.xll");

If you are calling the wrapper assembly from a COM client, you should usually distribute the type library file (.tlb) alongside the assembly (.dll) file.

If you are calling the wrapper assembly from a COM client, you must register the assembly as a COM module using regasm. Depending on your security policies, you may also need to sign the wrapper assembly, or add it to the GAC.

You must make the runtime library XllPlus.ComWrapper.Runtime.dll available.

If you are calling the wrapper assembly from a COM client, you should usually distribute the runtime type library file XllPlus.ComWrapper.Runtime.tlb alongside the assembly file.

If you are calling the wrapper assembly from a COM client, you must register the runtime assembly as a COM module using regasm.

You may find it convenient to add the runtime assembly to the GAC. If not, you should ensure a copy of the assembly is accessible to the client program (usually by placing it in the same directory as the client application).