In your career as a designer you will design many oddly sized and shaped boards including circular PCBs. You need the power of Altium Designer for these jobs.
Copper shorts can be identified with testing. Make sure you define test requirements in your PCB design software.
FR4 is by far the most popular set of PCB substrate materials. Here is how FR4 dielectric constant and your material properties will affect your next PCB.
For the best success when manufacturing your PCB design, you need the latest Gerber X2 file formats in the free Gerber file editor in your PCB design tools.
You can make the transition from being a hobby PCB maker to a professional designer when you use the best PCB design tools in Altium Designer.