Add-Ons are distributed as zip files.  To install them, simply save the zip file to My Documents/Blockland/Add-Ons (windows) or /Users/<username>/Documents/Blockland/Add-Ons (macintosh). If you use Steam, go to C:/Program Files (x86)/Steam/steamapps/Blockland/Add-Ons (If you have a 32 bit computer, go to Program Files as Program Files (x86) won't exist).  Do not extract the zip file.

Once an add-on is installed, you will have to enable if you want to use it in-game.

   To enable an add-on:

   * Start Blockland
   * Click "Start A Game"
   * Select the "Custom" Game Mode
   * Click "Select"
   * Check the Add-Ons that you want to use
   * Click "Select" again