Greetings, I need the team's advice to know if I am on the right track to designing an Arduino MEGA "shield", or if the approach I've used will yield a useless result.  Is there a better, more sensible approach? I am designing an Arduino MEGA "shield" - the PCB is populated with modules and components on the TOP side, and Male Header pins are populated on the BOTTOM side of the PCB, into which the Arduino MEGA plugs. * The top side works fine; you just place components per usual. * ~~In order to place the Arduino MEGA on the bottom side of the PCB it needs to be placed "upside down" from the perspective that EasyEDA normally takes.~~  When EasyEDA places a component on the bottom side the component is automatically Flipped, expecting that the bottom side of the component will be mounted to the bottom side of the PCB.  In the case of a "shield" I need to mount the top side of the component (Arduino Mega) to the bottom side of the PCB.  In order to accomplish this the PCB Layout of the Arduino MEGA needs to be Flipped in the 'X' direction.  Otherwise all the pins/connections are backwards and the Arduino MEGA will not fit.  Unfortunately, EasyEDA does not support Flipping of PCB components. So, what I am doing is telling EasyEDA that I am leaving the Arduino MEGA on the TOP side of the PCB.  This places all the pins in the correct locations and orientation; the male headers, when later added to the BOTTOM side, will plug right into the Arduino MEGA.  However, all the other modules and components are ALSO on the TOP side, so they are all superimposed on top of the Arduino MEGA. ~~As you can imagine, this creates lots of DRC errors.  This means that I will not be able to benefit from the automated DRC checks - I will have to carefully check everything manually, hoping that I don't overlook something~~ (this turned out not to be the case; error checking works great!).  ~~In order to help with this~~ I have created a Layout Prototype using a PCB Breadboard to check that everything fits.  BTW, I have also "stacked" a couple of things on the TOP side of the PCB - but I am less concerned about these, as they are much simpler to check. Here is a picture of what I've described - hopefully this helps visualize the approach:  Here's the segment of the PCB showing the messy result of the superimposed modules/components/Arduino MEGA:  What say you all? Best Regards, Ron Brinkman BTW - I Love, Love, Love EasyEDA.  It's unbelievably capable.