They're a bit busy developing the mod. Turms are found in the "Game / Data / Objects" folder generally, and could be copied into a separate mod, along with your submarines' UPC and EQP files, which would link the turms and equipment to the sub. Look in the current files for examples. There might be textures used on the turms & other gear down in the Texture folders, and other parts, such as guns up in the Library folder...