Setting Up The Child Theme Default Settings
Inside your Freelancer Child Theme you'll find a /lib/theme-defaults.php file. This file houses two functions that allow you to set the Freelancer Framework's "Theme Settings" default values upon both activation and reset.
By default the values are all commented out so no defaults are changed, but to configure this file to your own specific needs simply uncomment the options that you'd like to set, being sure to both tweak their values to your own custom defaults, as well as ensure that the same option/value has been uncommented and appropriately set in BOTH functions.
So to reiterate, if you only needed to set a custom "Pages Layout" value and nothing else, then you'd simply uncomment that option in both functions, tweak their values appropriately, save your changes, and you're done! To tweak two or three or four options you'd simply do the same for each option needed.
Once completed you should find that when your Child Theme is activated those custom values get set in the Freelancer "Theme Settings" admin page, and when you perform a settings reset inside that "Theme Settings" admin page they will reset to the Freelancer defaults, with your own custom defaults overriding those particular Freelancer values.