If you can design the connector placements of the base (mother) PCB on a grid (say 1mm or 0.1 inch. Don't make it any finer than you need.) and at least during the construction stages, set the origin to a point on this grid, then it should be easy to use the Distribute Array tool:  You can always reset the origin later. "Are there recommended approaches for creating the layout of the base PCB and then bringing the exact dimensions over to a daughter board?" Not sure why that is an issue. Surely the base and daughter board dimensions and placements are largely independent. You could draw the board outlines as DXF and import them. "...can I copy the pin headers from one PCB and paste them on another, and then associated them with the relevant items on the daughter board schematic?" Yes as long as you keep both Editor tabs open. Be careful though because you'll probably need to change the footprints associated with the headers on the daughter boards. 2) I think you need to read about Schematic and PCB Modules and then have a look at: [https://easyeda.com/forum/topic/Extension-User-Extensions-for-EasyEDA-Summary-9e065b68316f4491a3911dc6204be31e](https://easyeda.com/forum/topic/Extension-User-Extensions-for-EasyEDA-Summary-9e065b68316f4491a3911dc6204be31e)

@andyfierman Thank you for the guidance. I appreciate it!