Where do you have Silent Hunter installed? What is the "path" to it, in other words? When you run the install program, it defaults to "C:\Program Files (x86)\ Ubisoft\Silent Hunter Wolves of the Pacific\" - is your path like that, or did you change it? Also, did you install the DirectX v9.0c that came in the package?
Whichever folder that "SH4.exe" is in, is where you put the JSGME install (the easiest way). Run it from there, and it will create a "MODS" folder. Open the MODS folder, and put the desired mod in there. Back out to the game folder and use JSGME to activate the mod. Select the mod in the left column, click the arrow button in the middle that points to the right side. You might get prompted by JSGME, asking if you want to continue. Of course Windows UAC might also ask you some questions... It might take a while to activate the mod, depending on its size...
