QL does not need ANY actual information about YOUR cartridge. All it needs is accurate H20 capacity, enter the right barrel and bullet parameters, bullet shank seating depth and your powder load.
You could do this, manual entries for any cartridge(like with 223rem loaded for example), and it will work just fine. It's easier to begin with the same cal of your cartridge loaded(7mm), to get that cross sectional bore area pre-loaded.
You don't need QuickDesign.