At the bottom of Getting Started – PCB Builder | DigiKey Electronics there is a list of “Standard Board House Specifications”. There are some key parameters missing for DkRed:
Thickness of the lines used to draw the board outline. Does it need to match the router bit, or do you route to the middle of each line?
What clearance is required between pads and solder mask (aka “solder mask expansion”)
I would suggest looking at the design rules in Eagle or KiCad for a complete list.