this is a very huge set, it has almost 100 layers.
i also updated my how-to-use file.
this set has pipes and a layer called "pipe-copy-layer"
you can add your own pipes with this.
you need two layers for this and set grid to 20, set show grid and snap to grid.
in the first layer you copy the black parts of the right side. then you have to apply a background texture for this (you can use the mask-trick, see how-to-use file)
on a second layer you copy the left parts over the other parts.
when copying the second parts you have to be sure to copy all (there is the shadow of the pipe close to it)
the next set will be a trim again (like set7) and i planned an extra set with recolorable lights