The first post and the download page both have notes that the mod is only for the v1.5 of the SH4 game. That is basically the "Gold Edition", which was a euphemism for a all-in-one version of the game, which was originally released with a v1.x number (of course), and went through several interim updates, up through v1.4 that were US Pacific theatre-only versions of the game. Version 1.5 added several "features", including the German Type IX-D2 and Type XVIII U-Boats for a playable German career in the Monsun Gruppe, based in SE Asia. The basic "artwork" of the game was slightly changed, rendering the v1.5 "update" un-compatible with previous versions of the game, which also made all of the existing (at the time) mods incompatible. So, FotRSU is written to that "standard" and will not run in anything prior to v1.5. However, it does not matter whether you have a version of the game with the U-Boat Mission Add-On added on top of an older version of the game, the Steam, the Ubisoft, or any other download version, or the disk "Gold Edition" version of the game. If it says it is "Version 1.5" or "Gold Edition", that would be the same, and what you want. What you do have to do though, is ensure that the game is NOT installed in a Windows "Program Files" folder, or any other folder that Windows monitors. Otherwise, Windows itself will remove any updates and mods that you might add to the folder, and that is due to Windows "security" and the fact that the game was written for Windows XP, and is ignorant of anything about "Vista" or later versions of Windows. There are pdf files in the mod's Support folder, as well as other "help" peppered through-out the first post and the download page to help with game installation and mod activation. Or, any other questions, just post back and someone will help out.
