We will drill into the bottom side. So the parameter for x axis mirroring [-x] is used.
./fpcconvert.sh -c examples/niveaDice/fpcconvert.conf -xr examples/niveaDice/niveaDice.fpc -fgcode -o examples/niveaDice/niveaDice.bot.dri.ngc -lbottom
Following text is returned:
setting config file to examples/niveaDice/fpcconvert.conf
Warning: zero thickness for connection (4 -> 3), segment 1, net N000022
Warning: zero thickness for connection (2 -> 1), segment 1, net N000003
Warning: zero thickness for connection (3 -> 1), segment 1, net N000004
so library loaded, turbo GPC mode will be used
Warnings reported point to unconnected nets in the design, see figure Figure 2.3, “Project in FreePCB”. This is on purpose in this case.