Not sure.
Wix# has a direct support for registering assemblies in GAC (see GAC) sample. Though I am not sure what is the WiX recommended approach for managed-COM.
For native-COM you use
(see InjectXML sample).
This post has good description: http://stackoverflow.com/questions/364187/how-do-you-register-a-win32-com-dll-file-in-wix-3/364544#364544.
Though it is a question if the same approach will work for managed-COM.
Wix# has a direct support for registering assemblies in GAC (see GAC) sample. Though I am not sure what is the WiX recommended approach for managed-COM.
For native-COM you use
heat.exe to emit registration *.wxs, which you can then reference in Wix# project.AddWixFragment(... //or project.WixSourceGenerated += doc => doc.InjectWxs("CommonProperies.wxs");
This post has good description: http://stackoverflow.com/questions/364187/how-do-you-register-a-win32-com-dll-file-in-wix-3/364544#364544.
Though it is a question if the same approach will work for managed-COM.