The installation of the WTVP.NET is quite easy. It's based on the Microsoft Installer Technology. Before you start the installation I strongly recommend to read on the system requirements and the known bugs and problems. If for some reason you have a previous version installed I would suggest to uninstall it first.
When asked how to install please choose to install for Everyone:
Beside the fact that this is what I used here in my tests this makes sense: the Microsoft Visual C# wizard is installed in the Microsoft Visual Studio installation directory which normally is for everyone, too.
In addition to the Microsoft Visual C# 2005 you are asked for the path to the Watch TV Pro executable:
In constrast to Microsoft Visual C# 2005 this is a must. If you close this dialog without selecting any file the installation will abort. Now, the mechanism is not very intelligent since you can choose any file you like to make the installation continue. If you expect the wizard to work you must choose a file in a directory where the Watch TV Pro plugins directory is located as a direct child. So the application itself is a very good choice.
If for some reason Microsoft Visual C# 2005 is not found during the installation - the installer will check the local machine registry - no wizard is installed. If Microsoft Visual C# 2005 will be uninstalled after installing WTVP.NET and is installed again the wizard might be gone. In both cases after Microsoft Visual C# 2005 is (re)installed you may want to activate the wizard. This can be done manually although I would recommend to reinstall it.