Automating processes through a DMG file
I’m not aware of any autorun mechanism inside DMGs. You’re describing a scenario, however, which could probably be solved using a package installer. Packages can have file and folder payloads and may also contain pre and post installation scripts which are automatically executed as part of the installation process. 

Have a look at this freeware tool which allows you to comfortably create packages using the GUI:
http://s.sudre.free.fr/Software/Packages/about.html