There are a few mods that change the look of the "debris" involved, which is in the Library folder, appropriately named "debris.dat" file. Since there is no such thing as "gravity" in the 3D art world, it is difficult to have a "box" float appropriately, and I'm sure those partial "boxes" are supposed to represent boxes broken by the torpedo impact. A quick search of this site, and all I find is the SHIII version, but I know someone did one for SH4...
