Make sure 'Customize settings before installation' is ticked, then click 'Continue' Tick 'Continue without a source', then click 'Continue'
Once installed, run the following command to create a boot-modified OS X installer: iesd -i -o -t BaseSystemĬlick 'Install Windows or another OS from a DVD or image file', then click 'Continue' I would recommend setting the correct permissions on the required folder(s) instead.) Install iESD using the command 'gem install iesd' (You might need to 'sudo' this command depending on the write permissions you have set up. Make sure you have a legal copy of OS X 10.11 from the Mac App Store before doing this. Just spent a bit of time searching and hacking away (credits to for the modified installer technique).
