Need Help with creating a new CL type Comp

[barrsffc88]

Hello Fmer's

Need some help if possible please,

I started making a classic file like from the best team from a certain era, like 1992 onwards, i have 24 teams in a league, which is fine i have this all sorted, everything works.

But what i want to do is create a Champions League type cup for my league, so instead of having a FA cup and league cup i just want one cup. 

That being like the CL, but with 24 teams in the league i only want 16 teams to qualify, with no relegation in my league the teams below 16 will feel like relegation due to the amount of money they lose that season and not being in the Cup. 

When i try do this i have all types of problems, doesn't have a option to only allow the top 16 teams to qualify for it, also the groups and knockout stages i haven't got a clue what to do, Like i want say AC, REAL, ManU, Inter. to be seed 1, so they are in different groups but also i haven't a clue about that either.

Hope this is clear and would be thankful for the help, also a lot of work as gone into creating these players and teams, i'd also share the file after it's done. 

Thanks.