Ok. Lets start with basics. When you create and save database with the editor, you'll get .xml or .dbc file in your ( by default) documents/SI/FM14/editor data. In this folder, editor data, will be your created file. Also, if you download any other database, you need to place it also in documents/SI/FM14/editor data. Be careful, sometimes database is zipped or winrared, so you need to extract them. Best way to extract them is to download win rar or 7zip, install it if needed and then right click on downloaded database and choose 'extract here to 'name of the folder''. You will need to open that folder and copy ( or cut, or move) it to documents/SI/FM14/editor data. So if you just place .zip/.rar file or folder in documents/SI/FM14/editor data, it won't work.
Second step is to open your Football Manager, start new game and there, if you placed your database correctly, you'll get pop up window with some options like this:
Choose custom and then click on edit like presented on picture above.
After that, you'll get loading screen and thats perfectly normal. Then you'll get this:
View attachment 456013
There you'll find the name of the database you placed in 'editor data'. Choose it and click on OK/Confirm. And that's it. If its custom or new league, on next screen, when choosing leagues, you'll need to find that league and 'check' it. If the league has yellow exclamation mark, then your database is not correct, it's not good and there was mistake during its creation.
Maybe I should make this as a thread?
Also, pictures were taken from
Prodo.