WinBoard does not really need an install: you could put the winboard.exe file anywere, and it can run by itself. But if you want all the niceties like an entries in the start menu, and an extensive Windows help file describing all the features, you best start by installing the version from Tim Mann's website (link on the home page of this forum). IIRC that comes as a self-installing and unpacking executable. Then you can simply replace the winboard.exe by the one you download for WinBoard_F, and that one will be invoked when you use the icons in the start menu.
If there is no winboard.ini file in the folder you run WinBoard from, it will make one the first time you run it. (Just click that you want to use it as game viewer in the start-up dialog box.) This files saves all settings for the next time you run WinBoard. It also contains a list of Chess engines, from which you can coose in the startup dialog. (For engines not in the list you would have to type the name of their executable.) This is simplest if the engine executables are in the folder you run WinBoard from. Otherwise you need to type cumbersome path names, and what is worse, you will also have to tell WinBoard (by typing the /fd="..." or /sd="..."after the engine names) from which folder the engine should run (so it can find its opening book, or in case of Smirfoglot the SmirfEngine.dll).
If you want to add engines to the list you an select (originally only GNUChess will be there), just edit the winboard.ini file (e.g. using NotePad), look for the lines mentioning GNUChess, and add lines for other WB engines you have, exactly as you otherwise would have to type them in the start-up dialog fields.
Actually, it is highly recommended to download a tournament manager like PSWBTM (from Pradu's website). PSWBTM maintains a database of engines, which you can update in a very intuitive way through an engine-manager menu, and set up tournaments of various types between these engines. PSWBTM then takes care of passing all the necessary arguments to WinBoard, and you would hardly ever have to bother editing the winboard.ini file.
Note that there is a very good WinBoard FAQ on the website of Horizon (
http://www.horizonchess.com ).