There are subsystems that run in coords and Subsystems that are really just subobjects. A subsystem appears in Modview32 as a yellow cube. Open the POF-Editor in modview, and select the subsystems tab. Now create a new subsystem (create button), type in its name (for example, Engines, commincation, etc), your type is Real Subsystem (if you want it visable). You need to increase the radius to see it, fighters it can be something like 2-20, largeships it needs to be in the hundreds to thousands. Once you've increased the radius, you should see your yellow box in the center of the model. Now use logical guess and check with the 'center' fields (they are X, Y, and Z coordinates). to move it where you want it.
Im assuming you know how to table in the subsystem.
