CADWorx Plant ships with an Example.spc that has one entry for every component. The data files used with the Example.spc are located in the ..\CADWorxPlant\LIB_I\EXA\ directory.
The ZIP EXE download link (http://www.coade.com/cadworx/examplefiles.exe) has an updated set of these files and includes a drawing for each data file. Each drawing explains in more detail how the data file columns are used to generate the component graphics.
These drawings may help in understanding how CADWorx Plant uses the data file to draw the shape.
The ..\CADWorxPlant\Spec\DataFile.tbl file also has a listing of all data file columns used with different component type.