If you're having issues when saving the game, there are a few things we'd suggest trying to see if you can get this process to work successfully.
First of all, if within a save game try going to FM -> 'Save As'. When prompted to save, try saving to a different location than default (such as the desktop) and see if the game saves. If you can save there, then there is a problem with where your default Sports Interactive files are pointed, and we'd suggest changing your
Sometimes anti-virus setups can interfere with Steam and/or FM, so it's also worth reading and following the instructions here.
If you're having an issue where the game seems to be saving, but you can't see if within FM (only within the folder location) we would suggest changing the game save folder location, which can be done via the ‘Location’ option via the in-game preferences.
As a final warning, we would very much suggest NOT using any custom unofficial apps with the game, as these have not been tested and cannot be guaranteed to work. Any unofficial scouting or editing apps have the potential to cause severe problems.
If nothing above works, please submit a support request stating exactly what you've tried so far, and a member of our team will try to help.