Soo basiclly in my short exp as football manager i've noticed that the cup draws are pretty similar each season and i think i figured out how the engine works..
You should calculate the average quality of your 14 best players
If the number you get is equal to 5Stars average team then you'll most likely be getting a cup draw with
Your level players with same quality 5stars
One level higer players with average quality 4stars(appearing as 5stars to you)
Two level higer players with average quality of 3stars(appearing 5 stars to you)
If you'r 14players average quality is equal to 4Stars you'll be getting
One level lower teams with 5stars average quality
Same level players with same 4stars quality as yours.
One level higer teams with 3stars quality.
and so on.. If u'r average is 9Stars you'll be probabbly getting 4Stars(appearing 9 to you) teams that are 5 levels higer
example, if you'r lvl 1 with 9Stars Quality you'll face lvl 6 guys with 4Stars Q.
And 6 levels higer teams with 3Stars.
This is how the cup draw works for the first few level, i can only confirm thoes as im not as high level as other managers.
Please corect me if im wrong.
Could be moved to Tutorials and Guides, sry for posting in wrong section.