Q: My CAD have option to generate the pads as donuts, is it OK to send my files this way?
A: No, please don’t send pierced pads gerbers,

Q: What is Composite gerbers and negative plots, how bad are they for my design?
A: Composite layer is ancient way to generate your copper pour. This is still used by old CAD software which don’t have copper pour hatch stroke filling.

Q: I designed my board in Inch (mm) units, in which units should I export my Gerbers?
A: Always export your gerbers in the units you designed board to prevent rounding errors in your Gerber generation due to the unit conversion.

Q: What is good number precision for gerber generation?
A: 2.4 or 3.4

Q: My CAD ask me if I want to add offset to XY when I generate my Gerbers?
A: Please use offset 0,0