The first thing you will need to do is download a mod package from our forums. These mods are created by community members. Some mods may contain just a roster file while others contain a roster file and full graphical sets.
The first thing we would recommend is that if the file(s) you are downloading are in .zip format that you unzip them to a folder on your desktop so that you can find them to move them where they need to go. Some mod files may be setup as installers that will install things for you - if that is the case please see below on to where to install these items to.
We need to make sure the items end up in their proper locations. First find the folder where the game is installed. This typically would be C:/Wolverine Studios/DDSPB20xx although if you purchased the game from Steam it will have a different install path typically in C:/Program Files(x86)/Steam/steamapps/common/DDSPB20xx. Once that path is located find the setup folder. In that folder you will find an imports folder. Take the roster file with the .mdb extension and place it in that file.
If you are downloading graphical mods please note the graphics folder in the main file directory. This folder contains a number of subfolders each where specific items go. Find the folders where each type of items goes (logos, courts, etc) and place them in their proper locations.
To create the league open up the game and start a new league. Choose the custom option and select the .mdb file containing the rosters you wish to use when prompted. After that continue with league creation as normal. Also note that if you wish to have historical data as part of the league you will need to download a custom historical database. More information on that can be found in this article.