Hi Sandy,Originally posted in cdnusers.org by ejlersen
1. It is used for creating a drill layer that contains different symbols representing each drill size/type, normally this is not used for fabrication, here it is typical to use the Excellon drill files. You can make the PCB Editor auto generate different drill figures for each drill be using Manufacutre, NC, Drill Customization and pressing Auto generate symbols. Most people just send the Excellon files generated in Manufacture, NC, NC Drill - the drill figures are however good to get a visual view of the different drills on the pcb
2. Filmmask top and bottom are reserved for extra information that you could use, e.g., you could reserve it for glue, gold or whatever you may need.
I hope this helps.