Ensure you are using the 1.0 version of GTA San Andreas. Steam or Rockstar Launcher versions often require a downgrade to support most mods.
Before adding effects, you need these foundational tools to make the mods work: Download GTA San Andreas GTA Effects Mod GTA MOD Mafia rar
Necessary for executing custom scripts. Download the latest version from the official CLEO site. Ensure you are using the 1